[백준] 1920번 : 수 찾기

1920번: 수 찾기

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문제

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소스 코드

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Main {

    public static void main(String[] args) throws IOException{

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        int N = Integer.parseInt(br.readLine());
        int[] arr = new int[N];

        StringTokenizer st = new StringTokenizer(br.readLine());
        for (int i = 0; i < N; i++) {
            arr[i] = Integer.parseInt(st.nextToken());
        }

        Arrays.sort(arr);

        int M = Integer.parseInt(br.readLine());

        st = new StringTokenizer(br.readLine());

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < M; i++){
            if (binarySearch(arr, Integer.parseInt(st.nextToken())) >= 0) {
                sb.append(1).append('\n');
            }
            else sb.append(0).append('\n');
        }
        System.out.println(sb);
    }

    static int binarySearch(int[] arr, int key) {

        int lo = 0;
        int hi = arr.length - 1;

        while (lo <= hi) {

            int mid = (lo + hi) / 2;

            if (key < arr[mid]) {
                hi = mid - 1;
            }
            else if (key > arr[mid]) {
                lo = mid + 1;
            }
            else return mid;
        }

        return -1;
    }
}

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참고

[백준] 1920번 : 수 찾기 - JAVA [자바]