LuckBalance.js

'use strict';

const fs = require('fs');

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
    inputString += inputStdin;
});

process.stdin.on('end', function() {
    inputString = inputString.replace(/\s*$/, '')
        .split('\n')
        .map(str => str.replace(/\s*$/, ''));

    main();
});

function readLine() {
    return inputString[currentLine++];
}

// Complete the luckBalance function below.
function luckBalance(k, contests) {
       const arr = contests
        .slice()
        .sort((a, b) => b[0] - a[0]);

    const len = arr.length;
    let luck = 0, lost = k;

    for (let i = 0; i < len; i++) {
        const [value, important] = arr[i];
        // increment if lost, decrement if won
        if (important) {
            luck += lost > 0 ? value : -value;
            lost -= 1;
            continue;
        }
        // non-important are always lost
        luck += value;
    }

    return luck;


}

function main() {
    const ws = fs.createWriteStream(process.env.OUTPUT_PATH);

    const nk = readLine().split(' ');

    const n = parseInt(nk[0], 10);

    const k = parseInt(nk[1], 10);

    let contests = Array(n);

    for (let i = 0; i < n; i++) {
        contests[i] = readLine().split(' ').map(contestsTemp => parseInt(contestsTemp, 10));
    }

    const result = luckBalance(k, contests);

    ws.write(result + '\n');

    ws.end();
}