我试图理解quicksort和mergesort。
维基百科上写的快速排序步骤是：
Quicksort is a divide and conquer algorithm. Quicksort first divides a large list into two smaller sub-lists: the low elements and the high elements. Quicksort can then recursively sort the sub-lists.
The steps are:
Pick an element, called a pivot, from the list.
Reorder the list so that all elements with values less than the pivot come before the pivot, while all elements with values greater than the pivot come after it (equal values can go either way). After this partitioning, the pivot is in its final position. This is called the partition operation.
Recursively apply the above steps to the sub-list of elements with smaller values and separately the sub-list of elements with greater values.
这里快速排序使用pivot元素，而merge sort使用中间元素。
除此之外他们有何不同？ 感谢。