题解 | #合并表记录#

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
    let input = [];
    while(line = await readline()){
        input.push(line);
    }
    // 给的index值是索引，要求返回的值按照index升序，最好用数组去记录
    let arr = [];
    input.shift(); // 输入的键值对集合
    for (let item of input) {
        let key = item.split(' ')[0];
        let value = item.split(' ')[1];
        if (arr[key] === undefined) {
            arr[key] = parseInt(value);
        } else {
            arr[key] = arr[key] + parseInt(value);
        }
    }
    arr.forEach((item, index) => {
        if (item !== undefined) {
            console.log(`${index} ${item}`);
        }
    })
}()