Quick Sort

function partition(arr, start, end){
    // Taking the last element as the pivot
    const pivotValue = arr[end];
    let pivotIndex = start; 
    for (let i = start; i < end; i++) {
        if (arr[i] < pivotValue) {
        // Swapping elements
        [arr[i], arr[pivotIndex]] = [arr[pivotIndex], arr[i]];
        // Moving to next element
        pivotIndex++;
        }
    }
    
    // Putting the pivot value in the middle
    [arr[pivotIndex], arr[end]] = [arr[end], arr[pivotIndex]] 
    return pivotIndex;
};

function quickSort(arr, start, end) {
    // Base case or terminating case
    if (start >= end) {
        return;
    }
    
    // Returns pivotIndex
    let index = partition(arr, start, end);
    
    // Recursively apply the same logic to the left and right subarrays
    quickSort(arr, start, index - 1);
    quickSort(arr, index + 1, end);
}

quickSortRecursive(array, 0, array.length - 1)


[2, 5, 6, 9, 1, 8, 3, 5]

start = 0
end = 7

function quicksort(array) {
  if (array.length <= 1) {
    return array;
  }

  var pivot = array[0];
  
  var left = []; 
  var right = [];

  for (var i = 1; i < array.length; i++) {
    array[i] < pivot ? left.push(array[i]) : right.push(array[i]);
  }

  return quicksort(left).concat(pivot, quicksort(right));
};

var unsorted = [23, 45, 16, 37, 3, 99, 22];
var sorted = quicksort(unsorted);