[SW Expert Academy] 직사각형 길이 찾기 (D3)

https://swexpertacademy.com/main/solvingProblem/solvingProblem.do

SW Expert Academy

 

 

1. HashMap 사용

import java.util.HashMap;
import java.util.Map;
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++) {
			HashMap<Integer, Integer> map = new HashMap<>();

			for (int i = 0; i < 3; i++) {

				int num = sc.nextInt();

				map.put(num, map.getOrDefault(num, 0) + 1);

			}

			for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
				// System.out.println(entry.getValue());
				if (entry.getValue() % 2 != 0) {
					System.out.println("#" + tc + " " + entry.getKey());
				}
			}

		}

	}
}

 

 

2. 배열 arr 사용 

import java.util.Scanner;

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

		int t = sc.nextInt();

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

			int count[] = new int[101];

			for (int i = 0; i < 3; i++) {
				count[sc.nextInt()]++;
			}

			for (int i = 0; i <= 100; i++) {
				if (count[i] % 2 != 0) {
					System.out.println("#" + tc + " " + i);
					break;
				}
			}

		}

	}
}

 

3. 삼항연산자를 이용한 풀이

import java.util.Scanner;
class Main {
	public static void main(String args[]) throws Exception	{
		Scanner sc = new Scanner(System.in);
		int T = sc.nextInt();
		for(int tc = 1; tc <= T; tc++)
		{
            int a = sc.nextInt();
            int b = sc.nextInt();
            int c = sc.nextInt();
            int d = (a == b ? c : (a == c ? b : a));
            System.out.println("#" + tc + " " + d);
		}
	}
}

 

 

3번이 가장 바람직한 것 같다.

 

4. 비트연산자를 이용한 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 a = sc.nextInt();
			int b = sc.nextInt();
			int c = sc.nextInt();

			System.out.println("#"+tc+" "+(a^b^c));
		}

	}
}

 

 

import java.util.ArrayDeque;
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++) {
			ArrayDeque<Integer> q = new ArrayDeque<>();

			q.add(sc.nextInt());
			for (int i = 0; i < 2; i++) {
				int num = sc.nextInt();
				if (!q.isEmpty()&&num == q.peek())
					q.poll();
				else
					q.add(num);
			}
			
			System.out.println("#"+tc+" "+q.poll());
		}
	}
}

큐로 짝 찾기로도 가능