[BAEKJOON] 15655. N과 M (6)

 

문제링크

www.acmicpc.net/problem/15655

15655번: N과 M (6)

 

package acmicpc.Silver3;

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

public class N과_M6 {
	
	static int n;
	static int m;
	static int[] numbers;
	static int[] input;
	static StringBuilder sb;
	static boolean[] isSelected;
	
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine(), " ");
		
		n = Integer.parseInt(st.nextToken());
		m = Integer.parseInt(st.nextToken());
		numbers = new int[m];
		input = new int[n];
		
		st = new StringTokenizer(br.readLine(), " ");
		for(int i = 0 ; i < n ; i++) {
			input[i] = Integer.parseInt(st.nextToken());
		}
		Arrays.sort(input);
		isSelected = new boolean[n];
		sb = new StringBuilder();
		func(0, 0);
		System.out.println(sb);
	}
	
	public static void func(int cnt, int idx) {
		if (cnt == m) {
			for(int i : numbers) {
				sb.append(i + " ");
			}
			sb.setLength(sb.length() - 1);
			sb.append("\n");
			return;
		}
		
		for(int i = idx ; i < n ; i++) {
			if(isSelected[i]) continue;
			isSelected[i] = true;
			numbers[cnt] = input[i];
			func(cnt + 1, i + 1);
			isSelected[i] = false;
		}
	}
}

실행결과