Solution to See And Say - 50 Challenge

seeAndSay50.js

'use strict';

const debug = true;
const start = process.hrtime();

let seq = '1';
let results = [seq];
const runto = 50;

while (results.length < runto) {
    results.push(seeandsay(results[results.length - 1]));
}

console.log('sequence', results[results.length - 1]);
console.log('sum', sumdigits(results[results.length - 1]));

if (debug) {
    const end = process.hrtime(start);
    console.log('total took %d seconds and %d nanoseconds', end[0], end[1]);
}

function seeandsay(seq) {
    const start = process.hrtime();
    if (debug) {  }
    const parts = seq.split('');
    let count = 0;
    let last = parts[0];
    let newSeq = '';

    for (const part of parts) {
        if (part != last) {
            newSeq = newSeq.concat(count, last);
            count = 0;
            last = part;
        }
        count++;
    }

    newSeq = newSeq.concat(`${count}${last}`);

    if (debug) {
        const end = process.hrtime(start);
        console.log('seeandsay took %d seconds and %d nanoseconds', end[0], end[1]);
    }

    return newSeq;
}

function sumdigits(seq) {
    const start = process.hrtime();
    if (debug) { }
    const parts = seq.split('');

    let sum = 0;

    for (const part of parts) {
        sum += parseInt(part);
    }

    if (debug) {
        const end = process.hrtime(start);
        console.log('sumdigits took %d seconds and %d nanoseconds', end[0], end[1]);
    }

    return sum;
}