function getNext(x)
{
    let vals = x.toString().split('');
    let total = 0;
    for (let i = 0; i < vals.length; i++)
    {
        total += Math.pow(vals[i], vals.length);
    }
    return total;
}

function runSequenceFrom(startVal)
{
    let seq = [];
    let seqVals = new Set([]);
    let currentVal = startVal;

    while (!seqVals.has(currentVal))
    {
        seq.push(currentVal);
        seqVals.add(currentVal);
        currentVal = getNext(currentVal);
    }

    seq.push(currentVal);
    return seq;
}

function getLastSeqValFrom(x)
{
  return runSequenceFrom(x).pop();
}

function main(max)
{
    let totalEndingAt370 = 0;

    for (let i = 1; i < max; i++)
    {
        if (getLastSeqValFrom(i) === 370)
        {
            totalEndingAt370 += 1;
        }
    }

    return totalEndingAt370;
}

main(1000); // 529