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.*;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String c = sc.next();
		boolean a = false;
		out:for(int i = 0;i < c.length();i++) {
			for(int k = i+1;k < c.length();k++) {
				if(c.charAt(i)==c.charAt(k)) {
					System.out.println("No");
					a = true;
					break out;
				}
			}
		}
		if(a == false)System.out.println("Yes");
	}

}