[SW Expert Academy] 명진이와 동휘의 숫자 맞추기 (D3)

https://swexpertacademy.com/main/code/problem/problemDetail.do?contestProbId=AXBbOcTav0QDFAVg&categoryId=AXBbOcTav0QDFAVg&categoryType=CODE&problemTitle=%EB%AA%85%EC%A7%84&orderBy=FIRST_REG_DATETIME&selectCodeLang=ALL&select-1=&pageSize=10&pageIndex=1

SW Expert Academy

 

 

1 처음 풀이 

import java.util.Scanner;

class Solution {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		int t = sc.nextInt();
		for (int tc = 1; tc <= t; tc++) {

			int n = sc.nextInt();

			boolean[] check = new boolean[10];
			int[] focus = new int[4];
			int[] arr = new int[4];
			int[] cnt = new int[10];
			int flag = 0;

			for (int i = 0; i < check.length; i++) {
				check[i] = true;
			}

			for (int k = 0; k < n; k++) {

				for (int i = 0; i < 4; i++) {
					arr[i] = sc.nextInt();
				}

				String isPossible = sc.next();

				if (isPossible.equals("YES")) {
					for (int i = 0; i < 4; i++) {
						if (flag == 0)
							focus[i] = arr[i];
						cnt[arr[i]]++;
					}
					flag++;
				} else {
					for (int i = 0; i < 4; i++) {
						cnt[arr[i]]--;
						check[arr[i]] = false;
					}
				}
			}

			int max = Integer.MIN_VALUE;

			for (int i = 0; i < cnt.length; i++) {
				max = Math.max(max, cnt[i]);
			}

			boolean search = false;

			for (int i = 0; i < focus.length; i++) {
				if (check[focus[i]] == true && cnt[focus[i]] == max) {
					System.out.println("#" + tc + " " + focus[i]);
					search = true;
					break;
				}
			}

			if (!search) {
				for (int i = 0; i < check.length; i++) {
					if (check[i] == true) {
						System.out.println("#" + tc + " " + i);
						break;
					}
				}
			}

		}
	}
}

 

2. 두 번째 풀이

import java.util.HashSet;
import java.util.Scanner;

class Solution {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		int t = sc.nextInt();

		for (int tc = 1; tc <= t; tc++) {
			int n = sc.nextInt();

			HashSet<Integer> set = new HashSet<>();
			for (int i = 0; i < 10; i++) {
				set.add(i);
			}

			for (int i = 0; i < n; i++) {

				HashSet<Integer> call = new HashSet<>();

				for (int j = 0; j < 4; j++) {
					call.add(sc.nextInt());
				}

				String isPossible = sc.next();

				if (isPossible.equals("YES")) {
					set.retainAll(call);
				} else {
					set.removeAll(call);
				}
			}

			for (int num : set) {
				System.out.println("#" + tc + " " + num);
			}

		}
	}
}

https://kim-oriental.tistory.com/38

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https://godog.tistory.com/entry/Java-HashSet-%ED%95%A9%EC%A7%91%ED%95%A9-%EC%B0%A8%EC%A7%91%ED%95%A9-%EA%B5%90%EC%A7%91%ED%95%A9-%EB%B6%80%EB%B6%84%EC%A7%91%ED%95%A9

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