JAVA 코딩테스트 - 카카오 주차요금 계산

https://programmers.co.kr/learn/courses/30/lessons/92341

import java.util.*;

public class Solution {

    public int convert(String time) {
        String[] str = time.split(":");
        return Integer.parseInt(str[0]) * 60 + Integer.parseInt(str[1]);
    }

    public int[] solution(int[] fees, String[] records) {

        HashMap<String, Integer> intime = new HashMap<>();
        TreeMap<String, Integer> result = new TreeMap<>();      // 자동 정렬됨

        for (String r : records) {
            String[] str = r.split(" ");    // [0] : 시간, [1] : 차량번호, [2] : IN or OUT
            if (str[2].equals("IN")) {
                intime.put(str[1], convert(str[0]));    // 시:분 -> 분으로 convert
                if(!result.containsKey(str[1]))
                    result.put(str[1], 0);
            } else {
                result.put(str[1], result.get(str[1]) + convert(str[0]) - intime.get(str[1]));
                intime.remove(str[1]);
            }
        }
        // OUT 을 안 했을시 계산법
        intime.forEach((k,v) -> {
            result.put(k, result.get(k) + 23 * 60 + 59 - v);
        });

//        int[] answer = {};
        int[] answer = new int[result.size()];
        int idx = 0;
        for (int val : result.values()) {
            answer[idx] = fees[1];
            if (val > fees[0]) {
                answer[idx] += Math.ceil((val - fees[0]) / (double) fees[2]) * fees[3];
            }
            ++idx;
        }
        return answer;
    }
}

출처

https://www.youtube.com/watch?v=4vzfoIKs_Dw