Envío 4611

Código

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        boolean[] count = new boolean[26];
        String word = br.readLine();
        byte n = (byte) word.length();
        boolean yes = false;
        for (byte i = 0; i < n && !yes; i++) {
            if (count[word.charAt(i) - 'a']) {
                bw.write("yes\n");
                yes = true;
            } else {
                count[word.charAt(i) - 'a'] = true;
            }
        }
        if (!yes) {
            bw.write("no\n");
        }
        br.close();
        bw.close();
    }
}