/**

* get the digit at the given place value

* @param {number} num number

* @param {number} place place

* @return {number} digit in the given place

*/

function getDigit(num, place) {

return Math.floor(Math.abs(num) / Math.pow(10, place)) % 10;

}

/**

* get the number of digits in a number

* @param {number} num number

* @return {number} count of digits

*/

function digitCount(num) {

if (num === 0) return 1;

return Math.floor(Math.log10(Math.abs(num))) + 1;

}

/**

* get the number of digits in the largest number

* @param {array} nums numbers

* @return {number} count of digits

*/

function mostDigits(nums) {

let maxDigits = 0;

for (let i = 0; i < nums.length; i++) {

maxDigits = Math.max(maxDigits, digitCount(nums[i]));

}

return maxDigits;

}

/**

* Sort array using radix sort

* @param {array} arrOfNums array of unsorted numbers

* @return {array} Sorted array.

*/

function radixSort(arrOfNums) {

const maxDigitCount = mostDigits(arrOfNums);

for (let k = 0; k < maxDigitCount; k++) {

const digitBuckets = Array.from({length: 10}, () => []); // [[], [], [],...]

for (let i = 0; i < arrOfNums.length; i++) {

const digit = getDigit(arrOfNums[i], k);

digitBuckets[digit].push(arrOfNums[i]);

}

// New order after each loop

arrOfNums = [].concat(...digitBuckets);

}

return arrOfNums;

}

module.exports = radixSort;