[Java] 백준 6603번 : 로또

1. 문제

https://www.acmicpc.net/problem/6603

6603번: 로또

 

 

2. 풀이과정

K개 중에 6개를 뽑는 조합 문제이다.

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

public class Main {
    static int arr[], k;
    static StringBuilder sb;

    public static void combination(int start, int cnt, int visited){
        if(cnt==6){
            for(int i=0; i<k; i++){
                if((visited & (1<<i)) !=0){
                    sb.append(arr[i]).append(" ");
                }
            }
            sb.append("\n");
            return;
        }

        for(int i= start; i<k; i++){
            combination(i+1, cnt+1, visited | (1<<i));
        }
    }

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

        while(true){
            st = new StringTokenizer(br.readLine());
            k = Integer.parseInt(st.nextToken());
            if(k==0){break;}

            arr = new int[k];
            for(int i=0; i<k; i++){
                arr[i] = Integer.parseInt(st.nextToken());
            }

            combination(0, 0, 0);
            sb.append("\n");

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

 

결과