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 Rust (1.42.0) (judge verdict: Accepted)

use proconio::{fastout, input};
use std::collections::BTreeSet;

#[fastout]
fn main() {
    input! {s: String};
    let s: String = s;

    let mut v = Vec::new();

    for s_i in s.chars() {
        v.push(s_i);
    }
    let x = v.clone().len();

    v.sort();
    v.dedup();

    if x != v.len() {
        println!("no")
    } else {
        println!("yes")
    }
}