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.Scanner;

public class Main {
	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);

		String inputS = scanner.next();
		
		if(hasSameChar(inputS)) {
			System.out.println("no");
		}else {
			System.out.println("yes");
		}

		scanner.close();

	}

	static boolean hasSameChar(String inputS) {
		for (int i = 0; i < inputS.length() - 1; i++) {

			char buf = inputS.charAt(i);

			for (int j = 0; j < inputS.length() - 1; j++) {

				if (buf == inputS.charAt(j)) {
					return true;
				}

			}

		}
		
		return false;

	}

}