day2.html

<script>
    console.info('Part 1:', sum(
        fetchData().map(toGmax).filter(isPossible).map(g => g.n)
    ));
    console.info('Part 2:', sum(
        fetchData().map(toGmax).map(power)
    ));
    function sum(arr) {
        return arr.reduce((a, b) => a + +b, 0); // as numbers
    }
    function isPossible(gmax) {
        const pool = {
            r: 12,
            g: 13,
            b: 14
        };

        return gmax.r <= pool.r && gmax.g <= pool.g && gmax.b <= pool.b;
    }
    function toGmax(game) {
        const n = game.match(/Game (\d+)/)[1];

        return {
            n,
            r: max(game, 'red'),
            g: max(game, 'green'),
            b: max(game, 'blue')
        };
    }
    function max(game, color) {
        const re = new RegExp(`(\\d+) ${color}`, 'g');
        const nums = game.match(re).map(s => s.match(/\d+/)[0]);

        return Math.max(...nums);
    }
    function fetchData() {
        return `Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green
Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue
Game 3: 8 green, 6 blue, 20 red; 5 blue, 4 red, 13 green; 5 green, 1 red
Game 4: 1 green, 3 red, 6 blue; 3 green, 6 red; 3 green, 15 blue, 14 red
Game 5: 6 red, 1 blue, 3 green; 2 blue, 1 red, 2 green`.split(/\n/);
    }

    function power(gmax) {
        return gmax.r * gmax.b * gmax.g;
    }
</script>