text: #include <string.h>
  #define LINE_DELIMITERS "\n"
  #define WORD_DELIMITERS " " 
  
  static int wordcount(char *s) {
     int count = 1;
  
     if (strtok(s, WORD_DELIMITERS) == NULL)
        return 0;
     while (strtok(NULL, WORD_DELIMITERS) != NULL)
        count++;
     return count;
  }
  
  double wordaverage(char *s) {      /* return average size of words in s */
     int linecount = 1;
     char *nextline;
     int words;
  
     nextline = strtok(s, LINE_DELIMITERS);
     if (nextline == NULL)
        return 0.0;
     words = wordcount(nextline);
     while ((nextline = strtok(NULL, LINE_DELIMITERS)) != NULL) {
        words += wordcount(nextline);
        linecount++;
     }
     return (double)words/linecount;
  }
  