Untitled

#include <stdio.h>
#include <string.h>

int isLetters(char *alpha, int *frequency);

int main(void){
  char alpha[26];
  int frequency[26];
  char x;

  setOperation(alpha, frequency);
  while(x =! EOF){
        x = getchar();

        if( 'a' <= x && x <= 'z'){
                frequency[x-'a']++;
        }
}
        int l;
  for(l=0; l<26; l++){
        printf("%s, %d \n", alpha[l], frequency[l]);
}
  return 0;
}

int setOperation(char *alpha, int *frequency){
  int i, b;
  int a = 26;

  for(b=0; b < a; b++){
      alpha[b] = b + 'a';
          frequency[b]=0;
    }

  return 0;
}