text: 
  #line 3 "lex.yy.c"
  
  #define  YY_INT_ALIGNED short int
  
  /* A lexical scanner generated by flex */
  
  #define FLEX_SCANNER
  #define YY_FLEX_MAJOR_VERSION 2
  #define YY_FLEX_MINOR_VERSION 5
  #define YY_FLEX_SUBMINOR_VERSION 35
  #if YY_FLEX_SUBMINOR_VERSION > 0
  #define FLEX_BETA
  #endif
  
  /* First, we deal with  platform-specific or compiler-specific issues. */
  
  /* begin standard C headers. */
  #include <stdio.h>
  #include <string.h>
  #include <errno.h>
  #include <stdlib.h>
  
  /* end standard C headers. */
  
  /* flex integer type definitions */
  
  #ifndef FLEXINT_H
  #define FLEXINT_H
  
  /* C99 systems have <inttypes.h>. Non-C99 systems may or may not. */
  
  #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
  
  /* C99 says to define __STDC_LIMIT_MACROS before including stdint.h,
   * if you want the limit (max/min) macros for int types. 
   */
  #ifndef __STDC_LIMIT_MACROS
  #define __STDC_LIMIT_MACROS 1
  #endif
  
  #include <inttypes.h>
  typedef int8_t flex_int8_t;
  typedef uint8_t flex_uint8_t;
  typedef int16_t flex_int16_t;
  typedef uint16_t flex_uint16_t;
  typedef int32_t flex_int32_t;
  typedef uint32_t flex_uint32_t;
  typedef uint64_t flex_uint64_t;
  #else
  typedef signed char flex_int8_t;
  typedef short int flex_int16_t;
  typedef int flex_int32_t;
  typedef unsigned char flex_uint8_t; 
  typedef unsigned short int flex_uint16_t;
  typedef unsigned int flex_uint32_t;
  #endif /* ! C99 */
  
  /* Limits of integral types. */
  #ifndef INT8_MIN
  #define INT8_MIN               (-128)
  #endif
  #ifndef INT16_MIN
  #define INT16_MIN              (-32767-1)
  #endif
  #ifndef INT32_MIN
  #define INT32_MIN              (-2147483647-1)
  #endif
  #ifndef INT8_MAX
  #define INT8_MAX               (127)
  #endif
  #ifndef INT16_MAX
  #define INT16_MAX              (32767)
  #endif
  #ifndef INT32_MAX
  #define INT32_MAX              (2147483647)
  #endif
  #ifndef UINT8_MAX
  #define UINT8_MAX              (255U)
  #endif
  #ifndef UINT16_MAX
  #define UINT16_MAX             (65535U)
  #endif
  #ifndef UINT32_MAX
  #define UINT32_MAX             (4294967295U)
  #endif
  
  #endif /* ! FLEXINT_H */
  
  #ifdef __cplusplus
  
  /* The "const" storage-class-modifier is valid. */
  #define YY_USE_CONST
  
  #else	/* ! __cplusplus */
  
  /* C99 requires __STDC__ to be defined as 1. */
  #if defined (__STDC__)
  
  #define YY_USE_CONST
  
  #endif	/* defined (__STDC__) */
  #endif	/* ! __cplusplus */
  
  #ifdef YY_USE_CONST
  #define yyconst const
  #else
  #define yyconst
  #endif
  
  /* Returned upon end-of-file. */
  #define YY_NULL 0
  
  /* Promotes a possibly negative, possibly signed char to an unsigned
   * integer for use as an array index.  If the signed char is negative,
   * we want to instead treat it as an 8-bit unsigned char, hence the
   * double cast.
   */
  #define YY_SC_TO_UI(c) ((unsigned int) (unsigned char) c)
  
  /* Enter a start condition.  This macro really ought to take a parameter,
   * but we do it the disgusting crufty way forced on us by the ()-less
   * definition of BEGIN.
   */
  #define BEGIN (yy_start) = 1 + 2 *
  
  /* Translate the current start state into a value that can be later handed
   * to BEGIN to return to the state.  The YYSTATE alias is for lex
   * compatibility.
   */
  #define YY_START (((yy_start) - 1) / 2)
  #define YYSTATE YY_START
  
  /* Action number for EOF rule of a given start state. */
  #define YY_STATE_EOF(state) (YY_END_OF_BUFFER + state + 1)
  
  /* Special action meaning "start processing a new file". */
  #define YY_NEW_FILE yyrestart(yyin  )
  
  #define YY_END_OF_BUFFER_CHAR 0
  
  /* Size of default input buffer. */
  #ifndef YY_BUF_SIZE
  #define YY_BUF_SIZE 16384
  #endif
  
  /* The state buf must be large enough to hold one state per character in the main buffer.
   */
  #define YY_STATE_BUF_SIZE   ((YY_BUF_SIZE + 2) * sizeof(yy_state_type))
  
  #ifndef YY_TYPEDEF_YY_BUFFER_STATE
  #define YY_TYPEDEF_YY_BUFFER_STATE
  typedef struct yy_buffer_state *YY_BUFFER_STATE;
  #endif
  
  #ifndef YY_TYPEDEF_YY_SIZE_T
  #define YY_TYPEDEF_YY_SIZE_T
  typedef size_t yy_size_t;
  #endif
  
  extern yy_size_t yyleng;
  
  extern FILE *yyin, *yyout;
  
  #define EOB_ACT_CONTINUE_SCAN 0
  #define EOB_ACT_END_OF_FILE 1
  #define EOB_ACT_LAST_MATCH 2
  
      #define YY_LESS_LINENO(n)
      
  /* Return all but the first "n" matched characters back to the input stream. */
  #define yyless(n) \
  	do \
  		{ \
  		/* Undo effects of setting up yytext. */ \
          int yyless_macro_arg = (n); \
          YY_LESS_LINENO(yyless_macro_arg);\
  		*yy_cp = (yy_hold_char); \
  		YY_RESTORE_YY_MORE_OFFSET \
  		(yy_c_buf_p) = yy_cp = yy_bp + yyless_macro_arg - YY_MORE_ADJ; \
  		YY_DO_BEFORE_ACTION; /* set up yytext again */ \
  		} \
  	while ( 0 )
  
  #define unput(c) yyunput( c, (yytext_ptr)  )
  
  #ifndef YY_STRUCT_YY_BUFFER_STATE
  #define YY_STRUCT_YY_BUFFER_STATE
  struct yy_buffer_state
  	{
  	FILE *yy_input_file;
  
  	char *yy_ch_buf;		/* input buffer */
  	char *yy_buf_pos;		/* current position in input buffer */
  
  	/* Size of input buffer in bytes, not including room for EOB
  	 * characters.
  	 */
  	yy_size_t yy_buf_size;
  
  	/* Number of characters read into yy_ch_buf, not including EOB
  	 * characters.
  	 */
  	yy_size_t yy_n_chars;
  
  	/* Whether we "own" the buffer - i.e., we know we created it,
  	 * and can realloc() it to grow it, and should free() it to
  	 * delete it.
  	 */
  	int yy_is_our_buffer;
  
  	/* Whether this is an "interactive" input source; if so, and
  	 * if we're using stdio for input, then we want to use getc()
  	 * instead of fread(), to make sure we stop fetching input after
  	 * each newline.
  	 */
  	int yy_is_interactive;
  
  	/* Whether we're considered to be at the beginning of a line.
  	 * If so, '^' rules will be active on the next match, otherwise
  	 * not.
  	 */
  	int yy_at_bol;
  
      int yy_bs_lineno; /**< The line count. */
      int yy_bs_column; /**< The column count. */
      
  	/* Whether to try to fill the input buffer when we reach the
  	 * end of it.
  	 */
  	int yy_fill_buffer;
  
  	int yy_buffer_status;
  
  #define YY_BUFFER_NEW 0
  #define YY_BUFFER_NORMAL 1
  	/* When an EOF's been seen but there's still some text to process
  	 * then we mark the buffer as YY_EOF_PENDING, to indicate that we
  	 * shouldn't try reading from the input source any more.  We might
  	 * still have a bunch of tokens to match, though, because of
  	 * possible backing-up.
  	 *
  	 * When we actually see the EOF, we change the status to "new"
  	 * (via yyrestart()), so that the user can continue scanning by
  	 * just pointing yyin at a new input file.
  	 */
  #define YY_BUFFER_EOF_PENDING 2
  
  	};
  #endif /* !YY_STRUCT_YY_BUFFER_STATE */
  
  /* Stack of input buffers. */
  static size_t yy_buffer_stack_top = 0; /**< index of top of stack. */
  static size_t yy_buffer_stack_max = 0; /**< capacity of stack. */
  static YY_BUFFER_STATE * yy_buffer_stack = 0; /**< Stack as an array. */
  
  /* We provide macros for accessing buffer states in case in the
   * future we want to put the buffer states in a more general
   * "scanner state".
   *
   * Returns the top of the stack, or NULL.
   */
  #define YY_CURRENT_BUFFER ( (yy_buffer_stack) \
                            ? (yy_buffer_stack)[(yy_buffer_stack_top)] \
                            : NULL)
  
  /* Same as previous macro, but useful when we know that the buffer stack is not
   * NULL or when we need an lvalue. For internal use only.
   */
  #define YY_CURRENT_BUFFER_LVALUE (yy_buffer_stack)[(yy_buffer_stack_top)]
  
  /* yy_hold_char holds the character lost when yytext is formed. */
  static char yy_hold_char;
  static yy_size_t yy_n_chars;		/* number of characters read into yy_ch_buf */
  yy_size_t yyleng;
  
  /* Points to current character in buffer. */
  static char *yy_c_buf_p = (char *) 0;
  static int yy_init = 0;		/* whether we need to initialize */
  static int yy_start = 0;	/* start state number */
  
  /* Flag which is used to allow yywrap()'s to do buffer switches
   * instead of setting up a fresh yyin.  A bit of a hack ...
   */
  static int yy_did_buffer_switch_on_eof;
  
  void yyrestart (FILE *input_file  );
  void yy_switch_to_buffer (YY_BUFFER_STATE new_buffer  );
  YY_BUFFER_STATE yy_create_buffer (FILE *file,int size  );
  void yy_delete_buffer (YY_BUFFER_STATE b  );
  void yy_flush_buffer (YY_BUFFER_STATE b  );
  void yypush_buffer_state (YY_BUFFER_STATE new_buffer  );
  void yypop_buffer_state (void );
  
  static void yyensure_buffer_stack (void );
  static void yy_load_buffer_state (void );
  static void yy_init_buffer (YY_BUFFER_STATE b,FILE *file  );
  
  #define YY_FLUSH_BUFFER yy_flush_buffer(YY_CURRENT_BUFFER )
  
  YY_BUFFER_STATE yy_scan_buffer (char *base,yy_size_t size  );
  YY_BUFFER_STATE yy_scan_string (yyconst char *yy_str  );
  YY_BUFFER_STATE yy_scan_bytes (yyconst char *bytes,yy_size_t len  );
  
  void *yyalloc (yy_size_t  );
  void *yyrealloc (void *,yy_size_t  );
  void yyfree (void *  );
  
  #define yy_new_buffer yy_create_buffer
  
  #define yy_set_interactive(is_interactive) \
  	{ \
  	if ( ! YY_CURRENT_BUFFER ){ \
          yyensure_buffer_stack (); \
  		YY_CURRENT_BUFFER_LVALUE =    \
              yy_create_buffer(yyin,YY_BUF_SIZE ); \
  	} \
  	YY_CURRENT_BUFFER_LVALUE->yy_is_interactive = is_interactive; \
  	}
  
  #define yy_set_bol(at_bol) \
  	{ \
  	if ( ! YY_CURRENT_BUFFER ){\
          yyensure_buffer_stack (); \
  		YY_CURRENT_BUFFER_LVALUE =    \
              yy_create_buffer(yyin,YY_BUF_SIZE ); \
  	} \
  	YY_CURRENT_BUFFER_LVALUE->yy_at_bol = at_bol; \
  	}
  
  #define YY_AT_BOL() (YY_CURRENT_BUFFER_LVALUE->yy_at_bol)
  
  /* Begin user sect3 */
  
  #define yywrap(n) 1
  #define YY_SKIP_YYWRAP
  
  typedef unsigned char YY_CHAR;
  
  FILE *yyin = (FILE *) 0, *yyout = (FILE *) 0;
  
  typedef int yy_state_type;
  
  extern int yylineno;
  
  int yylineno = 1;
  
  extern char *yytext;
  #define yytext_ptr yytext
  
  static yy_state_type yy_get_previous_state (void );
  static yy_state_type yy_try_NUL_trans (yy_state_type current_state  );
  static int yy_get_next_buffer (void );
  static void yy_fatal_error (yyconst char msg[]  );
  
  /* Done after the current pattern has been matched and before the
   * corresponding action - sets up yytext.
   */
  #define YY_DO_BEFORE_ACTION \
  	(yytext_ptr) = yy_bp; \
  	yyleng = (yy_size_t) (yy_cp - yy_bp); \
  	(yy_hold_char) = *yy_cp; \
  	*yy_cp = '\0'; \
  	(yy_c_buf_p) = yy_cp;
  
  #define YY_NUM_RULES 33
  #define YY_END_OF_BUFFER 34
  /* This struct is not used in this scanner,
     but its presence is necessary. */
  struct yy_trans_info
  	{
  	flex_int32_t yy_verify;
  	flex_int32_t yy_nxt;
  	};
  static yyconst flex_int16_t yy_accept[70] =
      {   0,
          0,    0,   34,   32,   31,   31,   32,   21,   15,   16,
         19,   17,   18,   20,    1,   14,   23,   28,   22,   30,
         30,   30,   30,   30,   30,   30,   30,   12,   13,   31,
         27,    2,    1,   25,   26,   24,   30,   30,   30,   30,
         30,   30,    8,   30,   30,   30,   30,    2,   30,    6,
         30,   30,   30,    3,   30,   30,   30,    4,    7,    9,
         30,   11,   30,   30,    5,   30,   10,   29,    0
      } ;
  
  static yyconst flex_int32_t yy_ec[256] =
      {   0,
          1,    1,    1,    1,    1,    1,    1,    1,    2,    3,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    2,    4,    1,    1,    1,    5,    1,    1,    6,
          7,    8,    9,    1,   10,   11,   12,   13,   13,   13,
         13,   13,   13,   13,   13,   13,   13,    1,   14,   15,
         16,   17,    1,    1,   18,   18,   18,   18,   18,   18,
         18,   18,   18,   18,   18,   18,   18,   18,   18,   18,
         18,   18,   18,   18,   18,   18,   18,   18,   18,   18,
          1,    1,    1,    1,   19,    1,   20,   18,   21,   18,
  
         22,   23,   18,   24,   25,   18,   18,   26,   27,   28,
         29,   18,   18,   30,   31,   32,   33,   18,   34,   18,
         18,   18,   35,    1,   36,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
  
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1
      } ;
  
  static yyconst flex_int32_t yy_meta[37] =
      {   0,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    2,    1,    1,    1,    1,    2,    2,    2,
          2,    2,    2,    2,    2,    2,    2,    2,    2,    2,
          2,    2,    2,    2,    1,    1
      } ;
  
  static yyconst flex_int16_t yy_base[71] =
      {   0,
          0,    0,   84,   85,   35,   37,   67,   85,   85,   85,
         85,   85,   85,   85,   30,   85,   66,   65,   64,    0,
         20,   53,   52,   19,   57,   54,   51,   85,   85,   48,
         85,   61,   35,   85,   85,   85,    0,   53,   44,   38,
         39,   40,    0,   36,   42,   34,   40,   51,   33,    0,
         30,   39,   40,    0,   31,   25,   31,    0,    0,    0,
         24,    0,   25,   32,    0,   25,    0,    0,   85,   50
      } ;
  
  static yyconst flex_int16_t yy_def[71] =
      {   0,
         69,    1,   69,   69,   69,   69,   69,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   69,   69,   69,   70,
         70,   70,   70,   70,   70,   70,   70,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   70,   70,   70,   70,
         70,   70,   70,   70,   70,   70,   70,   69,   70,   70,
         70,   70,   70,   70,   70,   70,   70,   70,   70,   70,
         70,   70,   70,   70,   70,   70,   70,   70,    0,   69
      } ;
  
  static yyconst flex_int16_t yy_nxt[122] =
      {   0,
          4,    5,    6,    7,    8,    9,   10,   11,   12,   13,
          4,   14,   15,   16,   17,   18,   19,   20,    4,   20,
         21,   22,   23,   20,   24,   20,   25,   20,   20,   26,
         20,   20,   20,   27,   28,   29,   30,   30,   30,   30,
         32,   43,   33,   38,   39,   32,   44,   33,   40,   30,
         30,   37,   68,   67,   66,   65,   64,   63,   62,   61,
         60,   59,   58,   48,   57,   56,   55,   54,   53,   52,
         51,   50,   49,   48,   47,   46,   45,   42,   41,   36,
         35,   34,   31,   69,    3,   69,   69,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
  
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
         69
      } ;
  
  static yyconst flex_int16_t yy_chk[122] =
      {   0,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
          1,    1,    1,    1,    1,    1,    5,    5,    6,    6,
         15,   24,   15,   21,   21,   33,   24,   33,   21,   30,
         30,   70,   66,   64,   63,   61,   57,   56,   55,   53,
         52,   51,   49,   48,   47,   46,   45,   44,   42,   41,
         40,   39,   38,   32,   27,   26,   25,   23,   22,   19,
         18,   17,    7,    3,   69,   69,   69,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
  
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
         69,   69,   69,   69,   69,   69,   69,   69,   69,   69,
         69
      } ;
  
  static yy_state_type yy_last_accepting_state;
  static char *yy_last_accepting_cpos;
  
  extern int yy_flex_debug;
  int yy_flex_debug = 0;
  
  /* The intent behind this definition is that it'll catch
   * any uses of REJECT which flex missed.
   */
  #define REJECT reject_used_but_not_detected
  #define yymore() yymore_used_but_not_detected
  #define YY_MORE_ADJ 0
  #define YY_RESTORE_YY_MORE_OFFSET
  char *yytext;
  #line 1 "lab4.lx"
  #line 2 "lab4.lx"
  #include<stdlib.h>
  #include<string.h>
  #include<math.h>
  #include "y.tab.h"
  #line 505 "lex.yy.c"
  
  #define INITIAL 0
  
  #ifndef YY_NO_UNISTD_H
  /* Special case for "unistd.h", since it is non-ANSI. We include it way
   * down here because we want the user's section 1 to have been scanned first.
   * The user has a chance to override it with an option.
   */
  #include <unistd.h>
  #endif
  
  #ifndef YY_EXTRA_TYPE
  #define YY_EXTRA_TYPE void *
  #endif
  
  static int yy_init_globals (void );
  
  /* Accessor methods to globals.
     These are made visible to non-reentrant scanners for convenience. */
  
  int yylex_destroy (void );
  
  int yyget_debug (void );
  
  void yyset_debug (int debug_flag  );
  
  YY_EXTRA_TYPE yyget_extra (void );
  
  void yyset_extra (YY_EXTRA_TYPE user_defined  );
  
  FILE *yyget_in (void );
  
  void yyset_in  (FILE * in_str  );
  
  FILE *yyget_out (void );
  
  void yyset_out  (FILE * out_str  );
  
  yy_size_t yyget_leng (void );
  
  char *yyget_text (void );
  
  int yyget_lineno (void );
  
  void yyset_lineno (int line_number  );
  
  /* Macros after this point can all be overridden by user definitions in
   * section 1.
   */
  
  #ifndef YY_SKIP_YYWRAP
  #ifdef __cplusplus
  extern "C" int yywrap (void );
  #else
  extern int yywrap (void );
  #endif
  #endif
  
      static void yyunput (int c,char *buf_ptr  );
      
  #ifndef yytext_ptr
  static void yy_flex_strncpy (char *,yyconst char *,int );
  #endif
  
  #ifdef YY_NEED_STRLEN
  static int yy_flex_strlen (yyconst char * );
  #endif
  
  #ifndef YY_NO_INPUT
  
  #ifdef __cplusplus
  static int yyinput (void );
  #else
  static int input (void );
  #endif
  
  #endif
  
  /* Amount of stuff to slurp up with each read. */
  #ifndef YY_READ_BUF_SIZE
  #define YY_READ_BUF_SIZE 8192
  #endif
  
  /* Copy whatever the last rule matched to the standard output. */
  #ifndef ECHO
  /* This used to be an fputs(), but since the string might contain NUL's,
   * we now use fwrite().
   */
  #define ECHO fwrite( yytext, yyleng, 1, yyout )
  #endif
  
  /* Gets input and stuffs it into "buf".  number of characters read, or YY_NULL,
   * is returned in "result".
   */
  #ifndef YY_INPUT
  #define YY_INPUT(buf,result,max_size) \
  	if ( YY_CURRENT_BUFFER_LVALUE->yy_is_interactive ) \
  		{ \
  		int c = '*'; \
  		yy_size_t n; \
  		for ( n = 0; n < max_size && \
  			     (c = getc( yyin )) != EOF && c != '\n'; ++n ) \
  			buf[n] = (char) c; \
  		if ( c == '\n' ) \
  			buf[n++] = (char) c; \
  		if ( c == EOF && ferror( yyin ) ) \
  			YY_FATAL_ERROR( "input in flex scanner failed" ); \
  		result = n; \
  		} \
  	else \
  		{ \
  		errno=0; \
  		while ( (result = fread(buf, 1, max_size, yyin))==0 && ferror(yyin)) \
  			{ \
  			if( errno != EINTR) \
  				{ \
  				YY_FATAL_ERROR( "input in flex scanner failed" ); \
  				break; \
  				} \
  			errno=0; \
  			clearerr(yyin); \
  			} \
  		}\
  \
  
  #endif
  
  /* No semi-colon after return; correct usage is to write "yyterminate();" -
   * we don't want an extra ';' after the "return" because that will cause
   * some compilers to complain about unreachable statements.
   */
  #ifndef yyterminate
  #define yyterminate() return YY_NULL
  #endif
  
  /* Number of entries by which start-condition stack grows. */
  #ifndef YY_START_STACK_INCR
  #define YY_START_STACK_INCR 25
  #endif
  
  /* Report a fatal error. */
  #ifndef YY_FATAL_ERROR
  #define YY_FATAL_ERROR(msg) yy_fatal_error( msg )
  #endif
  
  /* end tables serialization structures and prototypes */
  
  /* Default declaration of generated scanner - a define so the user can
   * easily add parameters.
   */
  #ifndef YY_DECL
  #define YY_DECL_IS_OURS 1
  
  extern int yylex (void);
  
  #define YY_DECL int yylex (void)
  #endif /* !YY_DECL */
  
  /* Code executed at the beginning of each rule, after yytext and yyleng
   * have been set up.
   */
  #ifndef YY_USER_ACTION
  #define YY_USER_ACTION
  #endif
  
  /* Code executed at the end of each rule. */
  #ifndef YY_BREAK
  #define YY_BREAK break;
  #endif
  
  #define YY_RULE_SETUP \
  	YY_USER_ACTION
  
  /** The main scanner function which does all the work.
   */
  YY_DECL
  {
  	register yy_state_type yy_current_state;
  	register char *yy_cp, *yy_bp;
  	register int yy_act;
      
  #line 13 "lab4.lx"
  
  #line 689 "lex.yy.c"
  
  	if ( !(yy_init) )
  		{
  		(yy_init) = 1;
  
  #ifdef YY_USER_INIT
  		YY_USER_INIT;
  #endif
  
  		if ( ! (yy_start) )
  			(yy_start) = 1;	/* first start state */
  
  		if ( ! yyin )
  			yyin = stdin;
  
  		if ( ! yyout )
  			yyout = stdout;
  
  		if ( ! YY_CURRENT_BUFFER ) {
  			yyensure_buffer_stack ();
  			YY_CURRENT_BUFFER_LVALUE =
  				yy_create_buffer(yyin,YY_BUF_SIZE );
  		}
  
  		yy_load_buffer_state( );
  		}
  
  	while ( 1 )		/* loops until end-of-file is reached */
  		{
  		yy_cp = (yy_c_buf_p);
  
  		/* Support of yytext. */
  		*yy_cp = (yy_hold_char);
  
  		/* yy_bp points to the position in yy_ch_buf of the start of
  		 * the current run.
  		 */
  		yy_bp = yy_cp;
  
  		yy_current_state = (yy_start);
  yy_match:
  		do
  			{
  			register YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
  			if ( yy_accept[yy_current_state] )
  				{
  				(yy_last_accepting_state) = yy_current_state;
  				(yy_last_accepting_cpos) = yy_cp;
  				}
  			while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
  				{
  				yy_current_state = (int) yy_def[yy_current_state];
  				if ( yy_current_state >= 70 )
  					yy_c = yy_meta[(unsigned int) yy_c];
  				}
  			yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
  			++yy_cp;
  			}
  		while ( yy_base[yy_current_state] != 85 );
  
  yy_find_action:
  		yy_act = yy_accept[yy_current_state];
  		if ( yy_act == 0 )
  			{ /* have to back up */
  			yy_cp = (yy_last_accepting_cpos);
  			yy_current_state = (yy_last_accepting_state);
  			yy_act = yy_accept[yy_current_state];
  			}
  
  		YY_DO_BEFORE_ACTION;
  
  do_action:	/* This label is used only to access EOF actions. */
  
  		switch ( yy_act )
  	{ /* beginning of action switch */
  			case 0: /* must back up */
  			/* undo the effects of YY_DO_BEFORE_ACTION */
  			*yy_cp = (yy_hold_char);
  			yy_cp = (yy_last_accepting_cpos);
  			yy_current_state = (yy_last_accepting_state);
  			goto yy_find_action;
  
  case 1:
  YY_RULE_SETUP
  #line 14 "lab4.lx"
  yylval.integer = atoi(yytext); return INTEGER;
  	YY_BREAK
  case 2:
  YY_RULE_SETUP
  #line 15 "lab4.lx"
  yylval.real = atof(yytext); return REAL;
  	YY_BREAK
  case 3:
  YY_RULE_SETUP
  #line 17 "lab4.lx"
  return INT;
  	YY_BREAK
  case 4:
  YY_RULE_SETUP
  #line 18 "lab4.lx"
  return CHAR;
  	YY_BREAK
  case 5:
  YY_RULE_SETUP
  #line 19 "lab4.lx"
  return FLOAT;
  	YY_BREAK
  case 6:
  YY_RULE_SETUP
  #line 20 "lab4.lx"
  return CIN;
  	YY_BREAK
  case 7:
  YY_RULE_SETUP
  #line 21 "lab4.lx"
  return COUT;
  	YY_BREAK
  case 8:
  YY_RULE_SETUP
  #line 22 "lab4.lx"
  return IF;
  	YY_BREAK
  case 9:
  YY_RULE_SETUP
  #line 23 "lab4.lx"
  return ELSE;
  	YY_BREAK
  case 10:
  YY_RULE_SETUP
  #line 24 "lab4.lx"
  return WHILE;
  	YY_BREAK
  case 11:
  YY_RULE_SETUP
  #line 25 "lab4.lx"
  return MAIN;
  	YY_BREAK
  case 12:
  YY_RULE_SETUP
  #line 26 "lab4.lx"
  return OBRACE;
  	YY_BREAK
  case 13:
  YY_RULE_SETUP
  #line 27 "lab4.lx"
  return EBRACE;
  	YY_BREAK
  case 14:
  YY_RULE_SETUP
  #line 28 "lab4.lx"
  return SEMICOLON;
  	YY_BREAK
  case 15:
  YY_RULE_SETUP
  #line 29 "lab4.lx"
  return OPAR;
  	YY_BREAK
  case 16:
  YY_RULE_SETUP
  #line 30 "lab4.lx"
  return EPAR;
  	YY_BREAK
  case 17:
  YY_RULE_SETUP
  #line 31 "lab4.lx"
  return PLUS;
  	YY_BREAK
  case 18:
  YY_RULE_SETUP
  #line 32 "lab4.lx"
  return MINUS;
  	YY_BREAK
  case 19:
  YY_RULE_SETUP
  #line 33 "lab4.lx"
  return MULT;
  	YY_BREAK
  case 20:
  YY_RULE_SETUP
  #line 34 "lab4.lx"
  return DIV;
  	YY_BREAK
  case 21:
  YY_RULE_SETUP
  #line 35 "lab4.lx"
  return MOD;
  	YY_BREAK
  case 22:
  YY_RULE_SETUP
  #line 36 "lab4.lx"
  return GT;
  	YY_BREAK
  case 23:
  YY_RULE_SETUP
  #line 37 "lab4.lx"
  return LT;
  	YY_BREAK
  case 24:
  YY_RULE_SETUP
  #line 38 "lab4.lx"
  return GE;
  	YY_BREAK
  case 25:
  YY_RULE_SETUP
  #line 39 "lab4.lx"
  return LE;
  	YY_BREAK
  case 26:
  YY_RULE_SETUP
  #line 40 "lab4.lx"
  return EQ;
  	YY_BREAK
  case 27:
  YY_RULE_SETUP
  #line 41 "lab4.lx"
  return NOTEQ;
  	YY_BREAK
  case 28:
  YY_RULE_SETUP
  #line 42 "lab4.lx"
  return ASSIGN;
  	YY_BREAK
  case 29:
  YY_RULE_SETUP
  #line 43 "lab4.lx"
  return RETURN;
  	YY_BREAK
  case 30:
  YY_RULE_SETUP
  #line 44 "lab4.lx"
  yylval.text = strdup(yytext); return ID;
  	YY_BREAK
  case 31:
  /* rule 31 can match eol */
  YY_RULE_SETUP
  #line 46 "lab4.lx"
  /* ignore end of line and whitespace */
  	YY_BREAK
  case 32:
  YY_RULE_SETUP
  #line 47 "lab4.lx"
  {
    if(yytext[0] != 13){
    printf("Illegal token %s!\n",yytext);
    }
  }
  	YY_BREAK
  case 33:
  YY_RULE_SETUP
  #line 52 "lab4.lx"
  ECHO;
  	YY_BREAK
  #line 942 "lex.yy.c"
  case YY_STATE_EOF(INITIAL):
  	yyterminate();
  
  	case YY_END_OF_BUFFER:
  		{
  		/* Amount of text matched not including the EOB char. */
  		int yy_amount_of_matched_text = (int) (yy_cp - (yytext_ptr)) - 1;
  
  		/* Undo the effects of YY_DO_BEFORE_ACTION. */
  		*yy_cp = (yy_hold_char);
  		YY_RESTORE_YY_MORE_OFFSET
  
  		if ( YY_CURRENT_BUFFER_LVALUE->yy_buffer_status == YY_BUFFER_NEW )
  			{
  			/* We're scanning a new file or input source.  It's
  			 * possible that this happened because the user
  			 * just pointed yyin at a new source and called
  			 * yylex().  If so, then we have to assure
  			 * consistency between YY_CURRENT_BUFFER and our
  			 * globals.  Here is the right place to do so, because
  			 * this is the first action (other than possibly a
  			 * back-up) that will match for the new input source.
  			 */
  			(yy_n_chars) = YY_CURRENT_BUFFER_LVALUE->yy_n_chars;
  			YY_CURRENT_BUFFER_LVALUE->yy_input_file = yyin;
  			YY_CURRENT_BUFFER_LVALUE->yy_buffer_status = YY_BUFFER_NORMAL;
  			}
  
  		/* Note that here we test for yy_c_buf_p "<=" to the position
  		 * of the first EOB in the buffer, since yy_c_buf_p will
  		 * already have been incremented past the NUL character
  		 * (since all states make transitions on EOB to the
  		 * end-of-buffer state).  Contrast this with the test
  		 * in input().
  		 */
  		if ( (yy_c_buf_p) <= &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] )
  			{ /* This was really a NUL. */
  			yy_state_type yy_next_state;
  
  			(yy_c_buf_p) = (yytext_ptr) + yy_amount_of_matched_text;
  
  			yy_current_state = yy_get_previous_state(  );
  
  			/* Okay, we're now positioned to make the NUL
  			 * transition.  We couldn't have
  			 * yy_get_previous_state() go ahead and do it
  			 * for us because it doesn't know how to deal
  			 * with the possibility of jamming (and we don't
  			 * want to build jamming into it because then it
  			 * will run more slowly).
  			 */
  
  			yy_next_state = yy_try_NUL_trans( yy_current_state );
  
  			yy_bp = (yytext_ptr) + YY_MORE_ADJ;
  
  			if ( yy_next_state )
  				{
  				/* Consume the NUL. */
  				yy_cp = ++(yy_c_buf_p);
  				yy_current_state = yy_next_state;
  				goto yy_match;
  				}
  
  			else
  				{
  				yy_cp = (yy_c_buf_p);
  				goto yy_find_action;
  				}
  			}
  
  		else switch ( yy_get_next_buffer(  ) )
  			{
  			case EOB_ACT_END_OF_FILE:
  				{
  				(yy_did_buffer_switch_on_eof) = 0;
  
  				if ( yywrap( ) )
  					{
  					/* Note: because we've taken care in
  					 * yy_get_next_buffer() to have set up
  					 * yytext, we can now set up
  					 * yy_c_buf_p so that if some total
  					 * hoser (like flex itself) wants to
  					 * call the scanner after we return the
  					 * YY_NULL, it'll still work - another
  					 * YY_NULL will get returned.
  					 */
  					(yy_c_buf_p) = (yytext_ptr) + YY_MORE_ADJ;
  
  					yy_act = YY_STATE_EOF(YY_START);
  					goto do_action;
  					}
  
  				else
  					{
  					if ( ! (yy_did_buffer_switch_on_eof) )
  						YY_NEW_FILE;
  					}
  				break;
  				}
  
  			case EOB_ACT_CONTINUE_SCAN:
  				(yy_c_buf_p) =
  					(yytext_ptr) + yy_amount_of_matched_text;
  
  				yy_current_state = yy_get_previous_state(  );
  
  				yy_cp = (yy_c_buf_p);
  				yy_bp = (yytext_ptr) + YY_MORE_ADJ;
  				goto yy_match;
  
  			case EOB_ACT_LAST_MATCH:
  				(yy_c_buf_p) =
  				&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)];
  
  				yy_current_state = yy_get_previous_state(  );
  
  				yy_cp = (yy_c_buf_p);
  				yy_bp = (yytext_ptr) + YY_MORE_ADJ;
  				goto yy_find_action;
  			}
  		break;
  		}
  
  	default:
  		YY_FATAL_ERROR(
  			"fatal flex scanner internal error--no action found" );
  	} /* end of action switch */
  		} /* end of scanning one token */
  } /* end of yylex */
  
  /* yy_get_next_buffer - try to read in a new buffer
   *
   * Returns a code representing an action:
   *	EOB_ACT_LAST_MATCH -
   *	EOB_ACT_CONTINUE_SCAN - continue scanning from current position
   *	EOB_ACT_END_OF_FILE - end of file
   */
  static int yy_get_next_buffer (void)
  {
      	register char *dest = YY_CURRENT_BUFFER_LVALUE->yy_ch_buf;
  	register char *source = (yytext_ptr);
  	register int number_to_move, i;
  	int ret_val;
  
  	if ( (yy_c_buf_p) > &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars) + 1] )
  		YY_FATAL_ERROR(
  		"fatal flex scanner internal error--end of buffer missed" );
  
  	if ( YY_CURRENT_BUFFER_LVALUE->yy_fill_buffer == 0 )
  		{ /* Don't try to fill the buffer, so this is an EOF. */
  		if ( (yy_c_buf_p) - (yytext_ptr) - YY_MORE_ADJ == 1 )
  			{
  			/* We matched a single character, the EOB, so
  			 * treat this as a final EOF.
  			 */
  			return EOB_ACT_END_OF_FILE;
  			}
  
  		else
  			{
  			/* We matched some text prior to the EOB, first
  			 * process it.
  			 */
  			return EOB_ACT_LAST_MATCH;
  			}
  		}
  
  	/* Try to read more data. */
  
  	/* First move last chars to start of buffer. */
  	number_to_move = (int) ((yy_c_buf_p) - (yytext_ptr)) - 1;
  
  	for ( i = 0; i < number_to_move; ++i )
  		*(dest++) = *(source++);
  
  	if ( YY_CURRENT_BUFFER_LVALUE->yy_buffer_status == YY_BUFFER_EOF_PENDING )
  		/* don't do the read, it's not guaranteed to return an EOF,
  		 * just force an EOF
  		 */
  		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars) = 0;
  
  	else
  		{
  			yy_size_t num_to_read =
  			YY_CURRENT_BUFFER_LVALUE->yy_buf_size - number_to_move - 1;
  
  		while ( num_to_read <= 0 )
  			{ /* Not enough room in the buffer - grow it. */
  
  			/* just a shorter name for the current buffer */
  			YY_BUFFER_STATE b = YY_CURRENT_BUFFER;
  
  			int yy_c_buf_p_offset =
  				(int) ((yy_c_buf_p) - b->yy_ch_buf);
  
  			if ( b->yy_is_our_buffer )
  				{
  				yy_size_t new_size = b->yy_buf_size * 2;
  
  				if ( new_size <= 0 )
  					b->yy_buf_size += b->yy_buf_size / 8;
  				else
  					b->yy_buf_size *= 2;
  
  				b->yy_ch_buf = (char *)
  					/* Include room in for 2 EOB chars. */
  					yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2  );
  				}
  			else
  				/* Can't grow it, we don't own it. */
  				b->yy_ch_buf = 0;
  
  			if ( ! b->yy_ch_buf )
  				YY_FATAL_ERROR(
  				"fatal error - scanner input buffer overflow" );
  
  			(yy_c_buf_p) = &b->yy_ch_buf[yy_c_buf_p_offset];
  
  			num_to_read = YY_CURRENT_BUFFER_LVALUE->yy_buf_size -
  						number_to_move - 1;
  
  			}
  
  		if ( num_to_read > YY_READ_BUF_SIZE )
  			num_to_read = YY_READ_BUF_SIZE;
  
  		/* Read in more data. */
  		YY_INPUT( (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
  			(yy_n_chars), num_to_read );
  
  		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars);
  		}
  
  	if ( (yy_n_chars) == 0 )
  		{
  		if ( number_to_move == YY_MORE_ADJ )
  			{
  			ret_val = EOB_ACT_END_OF_FILE;
  			yyrestart(yyin  );
  			}
  
  		else
  			{
  			ret_val = EOB_ACT_LAST_MATCH;
  			YY_CURRENT_BUFFER_LVALUE->yy_buffer_status =
  				YY_BUFFER_EOF_PENDING;
  			}
  		}
  
  	else
  		ret_val = EOB_ACT_CONTINUE_SCAN;
  
  	if ((yy_size_t) ((yy_n_chars) + number_to_move) > YY_CURRENT_BUFFER_LVALUE->yy_buf_size) {
  		/* Extend the array by 50%, plus the number we really need. */
  		yy_size_t new_size = (yy_n_chars) + number_to_move + ((yy_n_chars) >> 1);
  		YY_CURRENT_BUFFER_LVALUE->yy_ch_buf = (char *) yyrealloc((void *) YY_CURRENT_BUFFER_LVALUE->yy_ch_buf,new_size  );
  		if ( ! YY_CURRENT_BUFFER_LVALUE->yy_ch_buf )
  			YY_FATAL_ERROR( "out of dynamic memory in yy_get_next_buffer()" );
  	}
  
  	(yy_n_chars) += number_to_move;
  	YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] = YY_END_OF_BUFFER_CHAR;
  	YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars) + 1] = YY_END_OF_BUFFER_CHAR;
  
  	(yytext_ptr) = &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[0];
  
  	return ret_val;
  }
  
  /* yy_get_previous_state - get the state just before the EOB char was reached */
  
      static yy_state_type yy_get_previous_state (void)
  {
  	register yy_state_type yy_current_state;
  	register char *yy_cp;
      
  	yy_current_state = (yy_start);
  
  	for ( yy_cp = (yytext_ptr) + YY_MORE_ADJ; yy_cp < (yy_c_buf_p); ++yy_cp )
  		{
  		register YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 1);
  		if ( yy_accept[yy_current_state] )
  			{
  			(yy_last_accepting_state) = yy_current_state;
  			(yy_last_accepting_cpos) = yy_cp;
  			}
  		while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
  			{
  			yy_current_state = (int) yy_def[yy_current_state];
  			if ( yy_current_state >= 70 )
  				yy_c = yy_meta[(unsigned int) yy_c];
  			}
  		yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
  		}
  
  	return yy_current_state;
  }
  
  /* yy_try_NUL_trans - try to make a transition on the NUL character
   *
   * synopsis
   *	next_state = yy_try_NUL_trans( current_state );
   */
      static yy_state_type yy_try_NUL_trans  (yy_state_type yy_current_state )
  {
  	register int yy_is_jam;
      	register char *yy_cp = (yy_c_buf_p);
  
  	register YY_CHAR yy_c = 1;
  	if ( yy_accept[yy_current_state] )
  		{
  		(yy_last_accepting_state) = yy_current_state;
  		(yy_last_accepting_cpos) = yy_cp;
  		}
  	while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
  		{
  		yy_current_state = (int) yy_def[yy_current_state];
  		if ( yy_current_state >= 70 )
  			yy_c = yy_meta[(unsigned int) yy_c];
  		}
  	yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
  	yy_is_jam = (yy_current_state == 69);
  
  	return yy_is_jam ? 0 : yy_current_state;
  }
  
      static void yyunput (int c, register char * yy_bp )
  {
  	register char *yy_cp;
      
      yy_cp = (yy_c_buf_p);
  
  	/* undo effects of setting up yytext */
  	*yy_cp = (yy_hold_char);
  
  	if ( yy_cp < YY_CURRENT_BUFFER_LVALUE->yy_ch_buf + 2 )
  		{ /* need to shift things up to make room */
  		/* +2 for EOB chars. */
  		register yy_size_t number_to_move = (yy_n_chars) + 2;
  		register char *dest = &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[
  					YY_CURRENT_BUFFER_LVALUE->yy_buf_size + 2];
  		register char *source =
  				&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move];
  
  		while ( source > YY_CURRENT_BUFFER_LVALUE->yy_ch_buf )
  			*--dest = *--source;
  
  		yy_cp += (int) (dest - source);
  		yy_bp += (int) (dest - source);
  		YY_CURRENT_BUFFER_LVALUE->yy_n_chars =
  			(yy_n_chars) = YY_CURRENT_BUFFER_LVALUE->yy_buf_size;
  
  		if ( yy_cp < YY_CURRENT_BUFFER_LVALUE->yy_ch_buf + 2 )
  			YY_FATAL_ERROR( "flex scanner push-back overflow" );
  		}
  
  	*--yy_cp = (char) c;
  
  	(yytext_ptr) = yy_bp;
  	(yy_hold_char) = *yy_cp;
  	(yy_c_buf_p) = yy_cp;
  }
  
  #ifndef YY_NO_INPUT
  #ifdef __cplusplus
      static int yyinput (void)
  #else
      static int input  (void)
  #endif
  
  {
  	int c;
      
  	*(yy_c_buf_p) = (yy_hold_char);
  
  	if ( *(yy_c_buf_p) == YY_END_OF_BUFFER_CHAR )
  		{
  		/* yy_c_buf_p now points to the character we want to return.
  		 * If this occurs *before* the EOB characters, then it's a
  		 * valid NUL; if not, then we've hit the end of the buffer.
  		 */
  		if ( (yy_c_buf_p) < &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] )
  			/* This was really a NUL. */
  			*(yy_c_buf_p) = '\0';
  
  		else
  			{ /* need more input */
  			yy_size_t offset = (yy_c_buf_p) - (yytext_ptr);
  			++(yy_c_buf_p);
  
  			switch ( yy_get_next_buffer(  ) )
  				{
  				case EOB_ACT_LAST_MATCH:
  					/* This happens because yy_g_n_b()
  					 * sees that we've accumulated a
  					 * token and flags that we need to
  					 * try matching the token before
  					 * proceeding.  But for input(),
  					 * there's no matching to consider.
  					 * So convert the EOB_ACT_LAST_MATCH
  					 * to EOB_ACT_END_OF_FILE.
  					 */
  
  					/* Reset buffer status. */
  					yyrestart(yyin );
  
  					/*FALLTHROUGH*/
  
  				case EOB_ACT_END_OF_FILE:
  					{
  					if ( yywrap( ) )
  						return 0;
  
  					if ( ! (yy_did_buffer_switch_on_eof) )
  						YY_NEW_FILE;
  #ifdef __cplusplus
  					return yyinput();
  #else
  					return input();
  #endif
  					}
  
  				case EOB_ACT_CONTINUE_SCAN:
  					(yy_c_buf_p) = (yytext_ptr) + offset;
  					break;
  				}
  			}
  		}
  
  	c = *(unsigned char *) (yy_c_buf_p);	/* cast for 8-bit char's */
  	*(yy_c_buf_p) = '\0';	/* preserve yytext */
  	(yy_hold_char) = *++(yy_c_buf_p);
  
  	return c;
  }
  #endif	/* ifndef YY_NO_INPUT */
  
  /** Immediately switch to a different input stream.
   * @param input_file A readable stream.
   * 
   * @note This function does not reset the start condition to @c INITIAL .
   */
      void yyrestart  (FILE * input_file )
  {
      
  	if ( ! YY_CURRENT_BUFFER ){
          yyensure_buffer_stack ();
  		YY_CURRENT_BUFFER_LVALUE =
              yy_create_buffer(yyin,YY_BUF_SIZE );
  	}
  
  	yy_init_buffer(YY_CURRENT_BUFFER,input_file );
  	yy_load_buffer_state( );
  }
  
  /** Switch to a different input buffer.
   * @param new_buffer The new input buffer.
   * 
   */
      void yy_switch_to_buffer  (YY_BUFFER_STATE  new_buffer )
  {
      
  	/* TODO. We should be able to replace this entire function body
  	 * with
  	 *		yypop_buffer_state();
  	 *		yypush_buffer_state(new_buffer);
       */
  	yyensure_buffer_stack ();
  	if ( YY_CURRENT_BUFFER == new_buffer )
  		return;
  
  	if ( YY_CURRENT_BUFFER )
  		{
  		/* Flush out information for old buffer. */
  		*(yy_c_buf_p) = (yy_hold_char);
  		YY_CURRENT_BUFFER_LVALUE->yy_buf_pos = (yy_c_buf_p);
  		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars);
  		}
  
  	YY_CURRENT_BUFFER_LVALUE = new_buffer;
  	yy_load_buffer_state( );
  
  	/* We don't actually know whether we did this switch during
  	 * EOF (yywrap()) processing, but the only time this flag
  	 * is looked at is after yywrap() is called, so it's safe
  	 * to go ahead and always set it.
  	 */
  	(yy_did_buffer_switch_on_eof) = 1;
  }
  
  static void yy_load_buffer_state  (void)
  {
      	(yy_n_chars) = YY_CURRENT_BUFFER_LVALUE->yy_n_chars;
  	(yytext_ptr) = (yy_c_buf_p) = YY_CURRENT_BUFFER_LVALUE->yy_buf_pos;
  	yyin = YY_CURRENT_BUFFER_LVALUE->yy_input_file;
  	(yy_hold_char) = *(yy_c_buf_p);
  }
  
  /** Allocate and initialize an input buffer state.
   * @param file A readable stream.
   * @param size The character buffer size in bytes. When in doubt, use @c YY_BUF_SIZE.
   * 
   * @return the allocated buffer state.
   */
      YY_BUFFER_STATE yy_create_buffer  (FILE * file, int  size )
  {
  	YY_BUFFER_STATE b;
      
  	b = (YY_BUFFER_STATE) yyalloc(sizeof( struct yy_buffer_state )  );
  	if ( ! b )
  		YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );
  
  	b->yy_buf_size = size;
  
  	/* yy_ch_buf has to be 2 characters longer than the size given because
  	 * we need to put in 2 end-of-buffer characters.
  	 */
  	b->yy_ch_buf = (char *) yyalloc(b->yy_buf_size + 2  );
  	if ( ! b->yy_ch_buf )
  		YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );
  
  	b->yy_is_our_buffer = 1;
  
  	yy_init_buffer(b,file );
  
  	return b;
  }
  
  /** Destroy the buffer.
   * @param b a buffer created with yy_create_buffer()
   * 
   */
      void yy_delete_buffer (YY_BUFFER_STATE  b )
  {
      
  	if ( ! b )
  		return;
  
  	if ( b == YY_CURRENT_BUFFER ) /* Not sure if we should pop here. */
  		YY_CURRENT_BUFFER_LVALUE = (YY_BUFFER_STATE) 0;
  
  	if ( b->yy_is_our_buffer )
  		yyfree((void *) b->yy_ch_buf  );
  
  	yyfree((void *) b  );
  }
  
  #ifndef __cplusplus
  extern int isatty (int );
  #endif /* __cplusplus */
      
  /* Initializes or reinitializes a buffer.
   * This function is sometimes called more than once on the same buffer,
   * such as during a yyrestart() or at EOF.
   */
      static void yy_init_buffer  (YY_BUFFER_STATE  b, FILE * file )
  
  {
  	int oerrno = errno;
      
  	yy_flush_buffer(b );
  
  	b->yy_input_file = file;
  	b->yy_fill_buffer = 1;
  
      /* If b is the current buffer, then yy_init_buffer was _probably_
       * called from yyrestart() or through yy_get_next_buffer.
       * In that case, we don't want to reset the lineno or column.
       */
      if (b != YY_CURRENT_BUFFER){
          b->yy_bs_lineno = 1;
          b->yy_bs_column = 0;
      }
  
          b->yy_is_interactive = file ? (isatty( fileno(file) ) > 0) : 0;
      
  	errno = oerrno;
  }
  
  /** Discard all buffered characters. On the next scan, YY_INPUT will be called.
   * @param b the buffer state to be flushed, usually @c YY_CURRENT_BUFFER.
   * 
   */
      void yy_flush_buffer (YY_BUFFER_STATE  b )
  {
      	if ( ! b )
  		return;
  
  	b->yy_n_chars = 0;
  
  	/* We always need two end-of-buffer characters.  The first causes
  	 * a transition to the end-of-buffer state.  The second causes
  	 * a jam in that state.
  	 */
  	b->yy_ch_buf[0] = YY_END_OF_BUFFER_CHAR;
  	b->yy_ch_buf[1] = YY_END_OF_BUFFER_CHAR;
  
  	b->yy_buf_pos = &b->yy_ch_buf[0];
  
  	b->yy_at_bol = 1;
  	b->yy_buffer_status = YY_BUFFER_NEW;
  
  	if ( b == YY_CURRENT_BUFFER )
  		yy_load_buffer_state( );
  }
  
  /** Pushes the new state onto the stack. The new state becomes
   *  the current state. This function will allocate the stack
   *  if necessary.
   *  @param new_buffer The new state.
   *  
   */
  void yypush_buffer_state (YY_BUFFER_STATE new_buffer )
  {
      	if (new_buffer == NULL)
  		return;
  
  	yyensure_buffer_stack();
  
  	/* This block is copied from yy_switch_to_buffer. */
  	if ( YY_CURRENT_BUFFER )
  		{
  		/* Flush out information for old buffer. */
  		*(yy_c_buf_p) = (yy_hold_char);
  		YY_CURRENT_BUFFER_LVALUE->yy_buf_pos = (yy_c_buf_p);
  		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars);
  		}
  
  	/* Only push if top exists. Otherwise, replace top. */
  	if (YY_CURRENT_BUFFER)
  		(yy_buffer_stack_top)++;
  	YY_CURRENT_BUFFER_LVALUE = new_buffer;
  
  	/* copied from yy_switch_to_buffer. */
  	yy_load_buffer_state( );
  	(yy_did_buffer_switch_on_eof) = 1;
  }
  
  /** Removes and deletes the top of the stack, if present.
   *  The next element becomes the new top.
   *  
   */
  void yypop_buffer_state (void)
  {
      	if (!YY_CURRENT_BUFFER)
  		return;
  
  	yy_delete_buffer(YY_CURRENT_BUFFER );
  	YY_CURRENT_BUFFER_LVALUE = NULL;
  	if ((yy_buffer_stack_top) > 0)
  		--(yy_buffer_stack_top);
  
  	if (YY_CURRENT_BUFFER) {
  		yy_load_buffer_state( );
  		(yy_did_buffer_switch_on_eof) = 1;
  	}
  }
  
  /* Allocates the stack if it does not exist.
   *  Guarantees space for at least one push.
   */
  static void yyensure_buffer_stack (void)
  {
  	yy_size_t num_to_alloc;
      
  	if (!(yy_buffer_stack)) {
  
  		/* First allocation is just for 2 elements, since we don't know if this
  		 * scanner will even need a stack. We use 2 instead of 1 to avoid an
  		 * immediate realloc on the next call.
           */
  		num_to_alloc = 1;
  		(yy_buffer_stack) = (struct yy_buffer_state**)yyalloc
  								(num_to_alloc * sizeof(struct yy_buffer_state*)
  								);
  		if ( ! (yy_buffer_stack) )
  			YY_FATAL_ERROR( "out of dynamic memory in yyensure_buffer_stack()" );
  								  
  		memset((yy_buffer_stack), 0, num_to_alloc * sizeof(struct yy_buffer_state*));
  				
  		(yy_buffer_stack_max) = num_to_alloc;
  		(yy_buffer_stack_top) = 0;
  		return;
  	}
  
  	if ((yy_buffer_stack_top) >= ((yy_buffer_stack_max)) - 1){
  
  		/* Increase the buffer to prepare for a possible push. */
  		int grow_size = 8 /* arbitrary grow size */;
  
  		num_to_alloc = (yy_buffer_stack_max) + grow_size;
  		(yy_buffer_stack) = (struct yy_buffer_state**)yyrealloc
  								((yy_buffer_stack),
  								num_to_alloc * sizeof(struct yy_buffer_state*)
  								);
  		if ( ! (yy_buffer_stack) )
  			YY_FATAL_ERROR( "out of dynamic memory in yyensure_buffer_stack()" );
  
  		/* zero only the new slots.*/
  		memset((yy_buffer_stack) + (yy_buffer_stack_max), 0, grow_size * sizeof(struct yy_buffer_state*));
  		(yy_buffer_stack_max) = num_to_alloc;
  	}
  }
  
  /** Setup the input buffer state to scan directly from a user-specified character buffer.
   * @param base the character buffer
   * @param size the size in bytes of the character buffer
   * 
   * @return the newly allocated buffer state object. 
   */
  YY_BUFFER_STATE yy_scan_buffer  (char * base, yy_size_t  size )
  {
  	YY_BUFFER_STATE b;
      
  	if ( size < 2 ||
  	     base[size-2] != YY_END_OF_BUFFER_CHAR ||
  	     base[size-1] != YY_END_OF_BUFFER_CHAR )
  		/* They forgot to leave room for the EOB's. */
  		return 0;
  
  	b = (YY_BUFFER_STATE) yyalloc(sizeof( struct yy_buffer_state )  );
  	if ( ! b )
  		YY_FATAL_ERROR( "out of dynamic memory in yy_scan_buffer()" );
  
  	b->yy_buf_size = size - 2;	/* "- 2" to take care of EOB's */
  	b->yy_buf_pos = b->yy_ch_buf = base;
  	b->yy_is_our_buffer = 0;
  	b->yy_input_file = 0;
  	b->yy_n_chars = b->yy_buf_size;
  	b->yy_is_interactive = 0;
  	b->yy_at_bol = 1;
  	b->yy_fill_buffer = 0;
  	b->yy_buffer_status = YY_BUFFER_NEW;
  
  	yy_switch_to_buffer(b  );
  
  	return b;
  }
  
  /** Setup the input buffer state to scan a string. The next call to yylex() will
   * scan from a @e copy of @a str.
   * @param yystr a NUL-terminated string to scan
   * 
   * @return the newly allocated buffer state object.
   * @note If you want to scan bytes that may contain NUL values, then use
   *       yy_scan_bytes() instead.
   */
  YY_BUFFER_STATE yy_scan_string (yyconst char * yystr )
  {
      
  	return yy_scan_bytes(yystr,strlen(yystr) );
  }
  
  /** Setup the input buffer state to scan the given bytes. The next call to yylex() will
   * scan from a @e copy of @a bytes.
   * @param bytes the byte buffer to scan
   * @param len the number of bytes in the buffer pointed to by @a bytes.
   * 
   * @return the newly allocated buffer state object.
   */
  YY_BUFFER_STATE yy_scan_bytes  (yyconst char * yybytes, yy_size_t  _yybytes_len )
  {
  	YY_BUFFER_STATE b;
  	char *buf;
  	yy_size_t n, i;
      
  	/* Get memory for full buffer, including space for trailing EOB's. */
  	n = _yybytes_len + 2;
  	buf = (char *) yyalloc(n  );
  	if ( ! buf )
  		YY_FATAL_ERROR( "out of dynamic memory in yy_scan_bytes()" );
  
  	for ( i = 0; i < _yybytes_len; ++i )
  		buf[i] = yybytes[i];
  
  	buf[_yybytes_len] = buf[_yybytes_len+1] = YY_END_OF_BUFFER_CHAR;
  
  	b = yy_scan_buffer(buf,n );
  	if ( ! b )
  		YY_FATAL_ERROR( "bad buffer in yy_scan_bytes()" );
  
  	/* It's okay to grow etc. this buffer, and we should throw it
  	 * away when we're done.
  	 */
  	b->yy_is_our_buffer = 1;
  
  	return b;
  }
  
  #ifndef YY_EXIT_FAILURE
  #define YY_EXIT_FAILURE 2
  #endif
  
  static void yy_fatal_error (yyconst char* msg )
  {
      	(void) fprintf( stderr, "%s\n", msg );
  	exit( YY_EXIT_FAILURE );
  }
  
  /* Redefine yyless() so it works in section 3 code. */
  
  #undef yyless
  #define yyless(n) \
  	do \
  		{ \
  		/* Undo effects of setting up yytext. */ \
          int yyless_macro_arg = (n); \
          YY_LESS_LINENO(yyless_macro_arg);\
  		yytext[yyleng] = (yy_hold_char); \
  		(yy_c_buf_p) = yytext + yyless_macro_arg; \
  		(yy_hold_char) = *(yy_c_buf_p); \
  		*(yy_c_buf_p) = '\0'; \
  		yyleng = yyless_macro_arg; \
  		} \
  	while ( 0 )
  
  /* Accessor  methods (get/set functions) to struct members. */
  
  /** Get the current line number.
   * 
   */
  int yyget_lineno  (void)
  {
          
      return yylineno;
  }
  
  /** Get the input stream.
   * 
   */
  FILE *yyget_in  (void)
  {
          return yyin;
  }
  
  /** Get the output stream.
   * 
   */
  FILE *yyget_out  (void)
  {
          return yyout;
  }
  
  /** Get the length of the current token.
   * 
   */
  yy_size_t yyget_leng  (void)
  {
          return yyleng;
  }
  
  /** Get the current token.
   * 
   */
  
  char *yyget_text  (void)
  {
          return yytext;
  }
  
  /** Set the current line number.
   * @param line_number
   * 
   */
  void yyset_lineno (int  line_number )
  {
      
      yylineno = line_number;
  }
  
  /** Set the input stream. This does not discard the current
   * input buffer.
   * @param in_str A readable stream.
   * 
   * @see yy_switch_to_buffer
   */
  void yyset_in (FILE *  in_str )
  {
          yyin = in_str ;
  }
  
  void yyset_out (FILE *  out_str )
  {
          yyout = out_str ;
  }
  
  int yyget_debug  (void)
  {
          return yy_flex_debug;
  }
  
  void yyset_debug (int  bdebug )
  {
          yy_flex_debug = bdebug ;
  }
  
  static int yy_init_globals (void)
  {
          /* Initialization is the same as for the non-reentrant scanner.
       * This function is called from yylex_destroy(), so don't allocate here.
       */
  
      (yy_buffer_stack) = 0;
      (yy_buffer_stack_top) = 0;
      (yy_buffer_stack_max) = 0;
      (yy_c_buf_p) = (char *) 0;
      (yy_init) = 0;
      (yy_start) = 0;
  
  /* Defined in main.c */
  #ifdef YY_STDINIT
      yyin = stdin;
      yyout = stdout;
  #else
      yyin = (FILE *) 0;
      yyout = (FILE *) 0;
  #endif
  
      /* For future reference: Set errno on error, since we are called by
       * yylex_init()
       */
      return 0;
  }
  
  /* yylex_destroy is for both reentrant and non-reentrant scanners. */
  int yylex_destroy  (void)
  {
      
      /* Pop the buffer stack, destroying each element. */
  	while(YY_CURRENT_BUFFER){
  		yy_delete_buffer(YY_CURRENT_BUFFER  );
  		YY_CURRENT_BUFFER_LVALUE = NULL;
  		yypop_buffer_state();
  	}
  
  	/* Destroy the stack itself. */
  	yyfree((yy_buffer_stack) );
  	(yy_buffer_stack) = NULL;
  
      /* Reset the globals. This is important in a non-reentrant scanner so the next time
       * yylex() is called, initialization will occur. */
      yy_init_globals( );
  
      return 0;
  }
  
  /*
   * Internal utility routines.
   */
  
  #ifndef yytext_ptr
  static void yy_flex_strncpy (char* s1, yyconst char * s2, int n )
  {
  	register int i;
  	for ( i = 0; i < n; ++i )
  		s1[i] = s2[i];
  }
  #endif
  
  #ifdef YY_NEED_STRLEN
  static int yy_flex_strlen (yyconst char * s )
  {
  	register int n;
  	for ( n = 0; s[n]; ++n )
  		;
  
  	return n;
  }
  #endif
  
  void *yyalloc (yy_size_t  size )
  {
  	return (void *) malloc( size );
  }
  
  void *yyrealloc  (void * ptr, yy_size_t  size )
  {
  	/* The cast to (char *) in the following accommodates both
  	 * implementations that use char* generic pointers, and those
  	 * that use void* generic pointers.  It works with the latter
  	 * because both ANSI C and C++ allow castless assignment from
  	 * any pointer type to void*, and deal with argument conversions
  	 * as though doing an assignment.
  	 */
  	return (void *) realloc( (char *) ptr, size );
  }
  
  void yyfree (void * ptr )
  {
  	free( (char *) ptr );	/* see yyrealloc() for (char *) cast */
  }
  
  #define YYTABLES_NAME "yytables"
  
  #line 52 "lab4.lx"
  
  
  int main_lex (argc,argv)
  int argc;
  char **argv;
  {
    ++argv;--argc;
    if( argc > 0) {
      yyin = fopen(argv[0],"r");
    }
    return 0;
  }
  
  