题解 | #整数与IP地址间的转换#

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void (async function () {
    const ip = await readline();
    const num = parseInt(await readline());
    const ipToNumber = (ip) => {
        let str = ip
            .split(".")
            .reduce(
                (pre, cur) => pre + Number(cur).toString(2).padStart(8, 0),
                ""
            );
        return parseInt(str, 2);
    };
    const numberToIp = (num) => {
        let str = num.toString(2).padStart(32, 0);
        let res = parseInt(str.slice(0, 8),2);
        for (let i = 8; i <= 24; i += 8) {
            res += "." + parseInt(str.slice(i, i + 8), 2);
        }
        return res;
    };
    console.log(ipToNumber(ip));
    console.log(numberToIp(num));
})();