aoc/2020/09/part1.js
2020-12-09 13:21:51 +00:00

21 lines
499 B
JavaScript

const fs = require('fs');
const data = fs.readFileSync('input.txt', 'utf-8');
const lines = data.split('\n').map(num => parseInt(num));
const preambleLength = 25;
let first
for (let i = preambleLength; i < lines.length; i++) {
valid = false
for (let j = i-preambleLength; j < i && !valid; j++) {
for (let k = j+1; k < i && !valid; k++) {
if (lines[j]+lines[k]== lines[i]) {
valid = true
}
}
}
if (!valid) {
first = lines[i]
break
}
}
console.log(first)