[백준] 15719 중복된 숫자 - Implementation / Java

• 문제 링크

https://www.acmicpc.net/problem/15719

 

• 풀이 코드

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

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        int n = read();
        boolean[] arr = new boolean[n];
        while (n-- > 0) {
            int i = read();
            if (arr[i]) {
                bw.write(String.valueOf(i));
                break;
            }
            arr[i] = true;
        }

        bw.flush();
    }

    private static int read() throws IOException {
        int c, n = System.in.read() & 15;
        while ((c = System.in.read()) > 32) n = (n << 3) + (n << 1) + (c & 15);

        return n;
    }

}