text: #include <stdio.h>
  #include <string.h>
  #include <math.h>
  
  int main(){
    
    char s[256];
    char inv[256];
    char freq[26];
    int i, len, pangram;
    float H,p;
  
    scanf("%[^\n]s",s);
  
    len = strlen(s);
    inv[len] = '\0';
  
    for( i=0;i<len;i++ ){
      inv[i] = s[len-i-1];
    }
    printf("%s\n",inv);
  
    for( i=0;i<26;i++ )
      freq[i]=0;
  
    for( i=0;i<len;i++ ){
      freq[tolower(s[i])-'a']++;
    }
  
    pangram = 1;
    for( i=0;i<26;i++ ){
      if( !freq[i] ){
        pangram=0;
        break;
      }
    }
  
    if( pangram )
      printf("É pangram\n");
    else
      printf("Não é pangram\n");
  
    H = 0.0;
    for( i=0;i<26;i++ ){
      if( freq[i] ){
        p = freq[i]/(float)len;
        H -= p*log(p)/log(2.0);
      }
    }
    printf("%f\n",H);
  
    return 0;
  }
  