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 (Clang 3.8.0) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <string.h>
int main(void)
{
char s[27]={0};
int i;
int x=0;
char temp;
scanf("%s",s);
temp=s[0];
for(i=0;i<strlen(s);i++){
	if(temp!=s[i]){
		x++;
		temp=s[i];
	}}
if(x+1==strlen(s)){
	
	printf("yes\n");
	
}else{
	printf("no\n");
}
	return 0;
}