Lucky ticket

lucky-ticket.js

(function(count){
    if (count % 2 !== 0) {
        throw Error('Must be even number');
    }

    const result = {};
    const length = count / 2;
    const sums = Array.from({length: Math.pow(9, length) / 2});
    const nums = Array.from({length: 10});
    const go = (l, m, n) => {
        if (l === 0) {
            if (Number(m) === n) {
                result[m] = result[m] ? result[m] + 1 : 1;
            }
        } else {
            for (const a in nums) {
                go(l - 1, m, Number(n) + Number(a));
            }
        }
    };

    for (const x in sums) {
        go(length, x, 0);
    }

    return Object.values(result).reduce((a, b) => a + Math.pow(b, 2), 0);
})(6)