[백준] N과 M (9) 15663 - JAVA

문제

https://www.acmicpc.net/problem/15663

15663번: N과 M (9)

 

코드

import java.io.*;
import java.util.*;

class Main {
	static int n, m;
	static int arr[];
	static int ans[];
	static boolean visited[];
	static StringBuilder sb = new StringBuilder();
	
	public static void main(String args[]) throws Exception{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));		
		StringTokenizer st = new StringTokenizer(br.readLine());
		
		n = Integer.parseInt(st.nextToken());
		m = Integer.parseInt(st.nextToken());
		
		arr = new int [n];
		ans = new int [m];
		visited = new boolean[n];
		
		st = new StringTokenizer(br.readLine());
		for(int i=0;i<n;i++) {
			arr[i] = Integer.parseInt(st.nextToken());
		}
		
		Arrays.sort(arr);
		back(0);
		System.out.print(sb);
	}
	
	static void back(int cnt) {
		if(cnt == m) {
			for(int i=0;i<cnt;i++) {
				sb.append(ans[i]+" ");
			}
			sb.append("\n");
			return;
		}
		int temp = 0;
		for(int i=0;i<n;i++) {
			if(!visited[i] && temp != arr[i]) {
				visited[i] = true;
				ans[cnt] = arr[i];
				temp = arr[i];
				back(cnt+1);
				visited[i] = false;
			}

		}
	}

}