[SW Expert Academy] 외로운 문자 (D3)

https://swexpertacademy.com/main/code/problem/problemDetail.do?problemLevel=3&contestProbId=AXVJuEvqLAADFASe&categoryId=AXVJuEvqLAADFASe&categoryType=CODE&problemTitle=&orderBy=PASS_RATE&selectCodeLang=ALL&select-1=3&pageSize=10&pageIndex=7

SW Expert Academy

 

import java.util.HashMap;
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++) {
			String str = sc.next();

			HashMap<Character, Integer> map = new HashMap<>();

			for (int i = 0; i < str.length(); i++) {
				map.put(str.charAt(i), map.getOrDefault(str.charAt(i), 0) + 1);
			}
			
			//System.out.println(map);
			
			boolean isExist=true;
			
			System.out.print("#"+tc+" ");

			for (int i = 0; i < 26; i++) {
				if (map.containsKey((char)('a' + i))) {
					if (map.get((char)('a' + i)) % 2 != 0) {
						isExist=false;
						System.out.print((char)('a' + i));
					}
				}
			}
			
			if(isExist==true) {
				System.out.print("Good");
			}
			
			System.out.println();

		}

	}
}

 

알파벳 소문자가 2로 나누어 떨어지는지를 hashmap으로 체크했다.

 

(char)('a'+i)는 char alpha로 치환을 해주면 더 깔끔해질 것 같다

 

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
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++) {
			String str = sc.next();

			HashMap<Character, Integer> map = new HashMap<>();
			ArrayList<Character> list = new ArrayList<>();
			
			for (int i = 0; i < str.length(); i++) {
				map.put(str.charAt(i), map.getOrDefault(str.charAt(i), 0) + 1);
			}
			
			for(char ch:map.keySet()) {
				if(map.get(ch)%2!=0) {
					list.add(ch);
				}
			}
			
			Collections.sort(list);
			
			System.out.print("#"+tc+" ");
			if(list.isEmpty()) {
				System.out.print("Good");
			}
			else {
				for(char ch:list) {
					System.out.print(ch);
				}
			}
			System.out.println();
			
			
			
		}

	}
}

 

 

cnt 활용한 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++) {
			String str = sc.next();
			StringBuilder sb = new StringBuilder();

			int cnt[] = new int[26];

			for (int i = 0; i < str.length(); i++) {
				cnt[str.charAt(i) - 'a']++;
			}

			for (int i = 0; i < 26; i++) {
				if (cnt[i] % 2 != 0) {
					sb.append((char) (i + 'a'));
				}
			}

			if (sb.toString().isEmpty()) {
				System.out.println("#" + tc + " " + "Good");
			} else {
				System.out.println("#" + tc + " " + sb);
			}

		}

	}
}