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: Accepted)

import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
	  Scanner sc = new Scanner(System.in);
	  String s = sc.next();
	  char [] str = s.toCharArray();
	  int c=0;
out:	  for(int i=0;i<str.length-1;i++) {
	    	   for(int j=i+1;j<str.length;j++) {
	    		   if(str[i]==str[j]) {
	    			   c++;
	    			   break out;
	    		   }
	    	   }
	  }

	 if(c==0)System.out.print("yes");
	 else System.out.print("no");
	 sc.close();
    }
}