算法：快速排序 

 1 # coding:utf-8
 2 
 3 import random
 4 import time
 5 
 6 t = time.time()
 7 
 8 # 快速排序的分割算法, 参考自编程珠玑
 9 # [l, r]为闭区间
10 def partion(a, l, r):
11     # tmp = a[0]
12     if l >= r:
13         return
14     m = l
15     #for i in range(1, len(a)):
16     for i in range(l + 1, r + 1):
17         if a[i] < a[l]:
18             m += 1
19             a[m], a[i] = a[i], a[m]
20 
21     a[l], a[m] = a[m], a[l]
22     partion(a, l, m - 1)
23     partion(a, m + 1, r)
24     return m
25 
26 #def qsort():
27 if __name__ == "__main__":
28     N = 100000
29     a = [random.randint(1,100000) for i in range(N)]
30     partion(a, 0, N - 1)
31     print a
32     b = a[:]; a.sort()
33     print b == a
34     print time.time() - t

 

快速排序的Python实现

参考文献：编程珠玑

posted @ 2015-08-29 23:31  bitpeng  阅读(191)  评论(0)  编辑  收藏  举报