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>
#include<string.h>

int main()
{
  char S[26];

  scanf("%s", S);

  if(S[1] != '\0')
  {
    for(int i=0; S[i] != '\0'; i++)
    {
      for(int j=i+1; S[j] != '\0'; j++)
      {
        if(S[i] == S[j])
        {
          printf("no\n");
          break;
          }
      }
      printf("yes\n");
    }
  }

  return 0;
}