의좋은 형제, 고장난 컴퓨터, 태민이의 취미

의좋은 형제

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import java.io.*;
class Main {
    private static int jinwoo;
    private static int sunwoo;

    public static void distribution(boolean dayChk) {
        if (dayChk) {
            sunwoo = (jinwoo % 2 == 0) ? (sunwoo + jinwoo / 2) : ((sunwoo + jinwoo / 2) + 1);
            jinwoo = jinwoo / 2;
        } else {
            jinwoo = (sunwoo % 2 == 0) ? (jinwoo + sunwoo / 2) : ((jinwoo + sunwoo / 2) + 1);
            sunwoo = sunwoo / 2;
        }
    }

    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] temp = br.readLine().split(" ");
        jinwoo = Integer.parseInt(temp[0]);
        sunwoo = Integer.parseInt(temp[1]);
        int day = Integer.parseInt(br.readLine());
        boolean startDayBool = true;

        for (int i = 0; i < day; i++) {
            distribution(startDayBool);
            startDayBool = !startDayBool;
        }

        System.out.println(jinwoo + " " + sunwoo);
    }
}

고장난 컴퓨터

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import java.io.*;
class Main {
    public static int recursiveRemainCharNumber() throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] temp = br.readLine().split(" ");
        int characterNumber = Integer.parseInt(temp[0]);
        int holdingTime = Integer.parseInt(temp[1]);
        String[] characters = br.readLine().split(" ");
        int remainCharNumber = 1;

        for (int i = 0; i <characterNumber - 1; i++) {
            if ((Integer.parseInt(characters[i + 1]) - Integer.parseInt(characters[i])) > holdingTime) {
                remainCharNumber = 1;
            } else {
                remainCharNumber++;
            }
        }
        return remainCharNumber;
    }

    public static void main(String[] args) throws IOException {
        int remainCharNumber = recursiveRemainCharNumber();
        System.out.println(remainCharNumber);
    }
}

태민이의 취미

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시그마 공식 세제곱으로 접근해서 해결해야 한다
반복문으로 코드 작성하면 실행 시간에 부하 발생

import java.io.*;
class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        long diceNumber = Integer.parseInt(br.readLine());
        long sum = diceNumber * (diceNumber + 1) / 2 % 1000000007L;
        long result = sum * sum % 1000000007L;
        System.out.println(result);
    }
}