[Baekjoon Online Judge] 2798 - 블랙잭 / Java

https://www.acmicpc.net/problem/2798

2798번: 블랙잭

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

public class Main {

	static int N, M, num[], isSelected[], answer = 0;

	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();

		StringTokenizer st = new StringTokenizer(br.readLine());
		N = Integer.parseInt(st.nextToken());
		M = Integer.parseInt(st.nextToken());
		num = new int[N];

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

		combination(0, 0, 0);
		System.out.println(answer);
	}

	private static void combination(int cnt, int start, int sum) {
		if (sum > M) {
			return;
		}

		if (cnt == 3) {
			if (sum == M) {
				answer = sum;
				return;
			} else if (sum < M) {
				if (sum > answer) {
					answer = sum;
				}
			}
			return;
		}

		for (int i = start; i < N; i++) {
			combination(cnt + 1, i + 1, sum + num[i]);
		}
	}
}