// Quick Sort Algorithm implemented in JS

function sort(arr, start, end){
    if (start >= end){
        return
    }

    let index = partition(arr, start, end);
    sort(arr, start, index - 1);
    sort(arr, index + 1, end);
}

function partition(arr, start, end) {
    let pivotIndex = start;
    let pivotValue = arr[end];

    for (let i = start; i < end; i++) {
        if (arr[i] < pivotValue){
            swap(arr, i, pivotIndex);
            pivotIndex++;
        }
    }
    swap(arr, pivotIndex, end);
    return pivotIndex;
}

function swap(arr, a, b){
    let temp = arr[a];
    arr[a] = arr[b];
    arr[b] = temp;
}