[JAVA] 백준 15656번- N과 M(7)

https://www.acmicpc.net/problem/15656

15656번: N과 M (7)

 

 

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 int n, m;
    public static int[] arr;
    public static int[] nums;
    public static StringBuilder sb = new StringBuilder();

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st;
        st = new StringTokenizer(br.readLine());

        n = Integer.parseInt(st.nextToken());
        m = Integer.parseInt(st.nextToken());

        arr = new int[m];
        nums = new int[n];

        st = new StringTokenizer(br.readLine());
        for (int i = 0; i < n; i++) {
            nums[i] = Integer.parseInt(st.nextToken());
        }
        Arrays.sort(nums);

        dfs(0);
        System.out.println(sb);
    }

    public static void dfs(int cnt) {
        if (cnt == m) {
            for (int val : arr) {
                sb.append(val).append(" ");
            }
            sb.append("\n");
            return;
        }
        for (int i = 0; i < n; i++) {
            arr[cnt] = nums[i];
            dfs(cnt + 1);
        }
    }
}

 

 

같은 수를 여러번 골라도 되므로 방문처리를 해주지 않아도 된다.