Problem:
Score : 200 points

Problem Statement

You are given a string S consisting of lowercase English letters. Determine whether all the characters in S are different.

Constraints

2 ≤ |S| ≤ 26, where |S| denotes the length of S.

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If all the characters in S are different, print yes (case-sensitive); otherwise, print no.

Sample Input 1

uncopyrightable

Sample Output 1

yes

Sample Input 2

different

Sample Output 2

no

Sample Input 3

no

Sample Output 3

yes

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(int argc, char const *argv[]) {
  char str1[27];
  scanf("%s", str1);

  for (size_t i = 0; i < sizeof(str1) / sizeof(str1[0]); i++) {
    if(str1[i] == '\0'){
      printf("Yes\n");
      return 0;
    }else if (str1[i] != str1[0]) {
      printf("No\n");
      return 0;
    }else{
      continue;
    }
  }
  return 0;
}