题解 | #整数与IP地址间的转换#

import java.util.Scanner;

import java.io.*;
public class Main {
    public static void main(String[] args) throws Exception {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        String ip = in.readLine();
        String ten = in.readLine();

        System.out.println(ip2ten(ip));
        System.out.println(ten2ip(ten));


    }

    private static String ip2ten(String ip) {
        String[] parts = ip.split("\\.");
        for (int i = 0; i < parts.length; i++) {
            parts[i] = Integer.toString(Integer.parseInt(parts[i]), 2);
            parts[i] = addZero(parts[i], 8);
        }
        String res = String.join("", parts);
        return Long.toString(Long.parseLong(res, 2), 10);
    }

    private static String ten2ip(String ten) {
        String str = Long.toString(Long.parseLong(ten), 2);
        str = addZero(str, 32);
        String[] parts = new String[4];
        for (int i = 0; i < 4; i++) {
            parts[i] = Integer.valueOf(str.substring(i * 8, (i + 1) * 8), 2).toString();
        }
        return String.join(".", parts);
    }

    private static String addZero(String str, int num) {
        if (str.length() >= num) {
            return str;
        }
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < num - str.length(); i++) {
            sb.append("0");
        }
        sb.append(str);
        return sb.toString();
    }
}