题解 | #截取字符串#

const readline = require('readline');

const data: string[] = [];

const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

rl.on('line', function (line) {
    data.push(line);
});

rl.on('close', () => {
    const cutStr = data[0].slice(0, Number(data[1]));
    console.log(cutStr);
})