Advent of Code 2024 Day 2

advent-code-2024-day2.js

const input = await fetch('https://adventofcode.com/2024/day/2/input').then(res => res.text()).then(data => data.trim());

console.log(input);

const data = input.split('\n').map(val => val.split(' ').map((str) => parseInt(str, 10)))

// console.log(data);

const safeCount = data.reduce((acc, arr) => {
    if (arr[0] - arr[1] === 0) {
        return acc
    }
    
    let isSafe = true;
    let dir = arr[0] - arr[1] > 0 ? 'down' : 'up';

    // console.log(dir)

    for (let i=0; i<arr.length - 1; i++) {
        if (arr[i] - arr[i+1] === 0) {
            isSafe = false;
            break;
        }
        
        if (dir === 'down') {
            const delta = arr[i] - arr[i+1];
            // console.log({delta});

            if (delta < 1 || delta > 3) {
                // console.log(arr, 'down not safe');
                isSafe = false;
                break;
            }
        }

        if (dir === 'up') {
            const delta = arr[i+1] - arr[i];
            // console.log({delta});

            if (delta < 1 || delta > 3) {
                // console.log(arr, 'up not safe');
                isSafe = false;
                break;
            }
        }
    }

    if (isSafe) {
        // console.log(arr, 'is safe')
        safe.push(arr)
        return acc + 1
    }
    return acc
}, 0)

console.log({safeCount})