7-4 Stack depth for quicksort The QUICKSORT algorithm of Section 7.1 contains two recursive calls to itself. After QUICK SORT calls PARTITION, it recursively sorts the left subarray and then it recursively sorts the right subarray. The second recursive call in QUICKSORT is not really necessary; we can avoid it by using an iterative control structure This technique, called tail recursion, is provided automatically by good compilers. Consider the following version of quicksort, which simulates tail recursion: TAIL-RECURSIVE-QUICKSORT (A, p.r) 1 while p