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(void){
        int i,j;
        char S[25];
        scanf("%s",S);
        for(i=0;i<25;i++){
            for(j=i;j<25;++j){
                if(S[i]==S[j]){
                 printf("no\n");
                 break;
                }
                else if(i==24&&j==24){
                         printf("yes\n");
                         break;
                }
            }
            if(S[i]==S[j]){
             break;
           }
        }
	return 0;
}