[백준-자바] 1940번 주몽 / 2022.05.21

 

https://www.acmicpc.net/problem/1940

1940번: 주몽

 

 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

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()); // 재료의 개수 N
        int M = Integer.parseInt(br.readLine()); // 갑옷을 만드는데 필요한 수 M

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

        int count = 0;
        for(int i=0; i<N-1; i++){
            for(int j=i+1; j<N; j++){
                if(material[i]+material[j]==M)
                    count++;
            }
        }

        System.out.println(count);
    }
}