const rl = require("readline").createInterface({ input: process.stdin }); var iter = rl[Symbol.asyncIterator](); const readline = async () => (await iter.next()).value; void (async function () { // Write your code here while ((line = await readline())) { // 方法1: // let arr = line.split(''); // console.log(arr.reverse().join('')); // 方法2: let str = ""; for (i = line.length - 1; i >= 0; i--) { str += line[i]; } console.log(str); } })();