Quick sort
High level code are quite simple ( divide/conque, recursively partition the array):
void quickSort(int arr[], int low, int high){ if (low < high) { /* pi is partitioning index, arr[p] is now at right place */ int pi = partition(arr, low, high); // Separately sort elements before // partition and after partition quickSort(arr, low, pi - 1); quickSort(arr, pi + 1, high); }}The key is how to partition in-place?
Here a pretty good quick sort ( random pivot ) video , keep l, r index
There are some other partition strategy like always choose the last or first element.
http://www.geeksforgeeks.org/merge-sort/
