const fs = require('fs') const readline = require('readline'); const readInterface = readline.createInterface({ input: fs.createReadStream('input'), console: false }); let numbers = []; readInterface.on('line', function(line) { numbers.push(Number(line)); }); readInterface.on('close', function(line) { numbers.forEach(function(a) { numbers.forEach(function(b) { numbers.forEach(function(c) { if (a + b + c == 2020) { console.log(a*b*c); process.exit(); } }); }); }); });