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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;

int main() {
  string N;
  cin >> N;
  int count = 0;
  int K;
  K = N.size();
  for(int i = 0; i < K-1; i++){
     for(int j = 0; j < K-1; j++){
      if(N.at(i) == N.at(j)){
          count++;
      }
    }
  }
  if(count > K-1){
      cout << "no" << endl;
  }
  else cout << "yes" << endl;
}