Sort

var sortArray = function(nums) {
    quickSort(nums, 0, nums.length-1)
    return nums
};

function quickSort(arr, start, end) {
    if(start < end) {
        const pivot = partition(arr, start, end)
        quickSort(arr, start, pivot - 1)
        quickSort(arr, pivot + 1, end)
    }
}

function partition(arr, start, end) {
    const pivot = arr[start]
    let i=start, j=end
    while(i < j) {
        while(i < j && arr[j] >= pivot)
            j--
        arr[i] = arr[j]
        while(i < j && arr[i] < pivot)
            i++
        arr[j] = arr[i]
    }
    arr[i] = pivot
    return i
}