PARTITION(A, p, r)
代码如下:
x ← A[r]
i ← p - 1
for j ← p to r - 1
do if A[j] ≤ x
then i ← i + 1
swap(A[i], A[j])
swap(A[i + 1], A[r])
return i + 1
QUICKSORT(A, p, r)
代码如下:
if p < r
then q ← PARTITION(A, p, r)
QUICKSORT(A, p, q - 1)
QUICKSORT(A, q + 1, r)
实现：
代码如下:
#!/usr/bin/python
import sys
def partion(array, p, r):
x = array[r]
i = p - 1
for j in range(p, r):
if (array[j] < x):
i+=1
array[j], array[i] = array[i], array[j]
i+=1
array[i], array[r] = array[r], array[i]
return i
def quick_sort(array, p, r):
if p < r:
q = partion(array, p, r)
quick_sort(array, p, q - 1)
quick_sort(array, q + 1, r)
if __name__ == "__main__":
array = [1, 3, 5, 23, 64, 7, 23, 6, 34, 98, 100, 9]
quick_sort(array, 0, len(array) - 1)
for a in array:
sys.stdout.write("%d " % a)