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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

 import java.util.*;
import java.lang.*;
 
public class Main {
    public static void main(String[] args) {
 
        Scanner sc  = new Scanner(System.in);
 
        String S = sc.next();
        int f = 0;
        char[] c = S.toCharArray();

        for(int i = 0 ; i < S.length() ; i++) {
            
      //  System.out.println((int)c[i]);
        }
        
        int[] test  = new int[1000];        
        for(int i = 0; i < S.length(); i++){
            test[c[i]]++;
        }
        for(int i = 0; i < 1000; i++){
          
            if(test[i]>=2) f++;
        }
 
 
 
        if(f>=2) System.out.print("no");
        else    System.out.print("yes");
        System.out.println();
    }
 
}