题解 | 截取字符串

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



void async function () {
    let s = await readline();
    let k = parseInt(await readline());
    console.log(s.substring(0, k)); 
}();

赫赫主要难度在研究怎么处理多行输入上，我真的不太熟悉ACM模式下怎么写