R.elem[0] = R.elem[low]; pivotkey = R.elem[low].key;
时间: 2024-01-06 13:05:46 浏览: 31
These two lines of code are part of the partitioning process in the quicksort algorithm.
The first line sets the value of the first element in the array (R.elem[0]) to the value of the element at the low index position. This is done to make sure that the pivot element (which will be chosen at the low index position) is moved to the beginning of the array.
The second line sets the value of pivotkey to the key value of the pivot element. The key is typically used to compare elements during the partitioning process. The pivot element is chosen as a reference point to partition the array into two halves: elements smaller than the pivot are moved to the left of it, and elements larger than the pivot are moved to the right of it.
Overall, these two lines of code are used to set up the initial state of the partitioning process by choosing the pivot element and moving it to the beginning of the array.