欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  IT编程

Python字符串匹配算法KMP实例

程序员文章站 2023-12-11 23:34:22
本文实例讲述了Python字符串匹配算法KMP。分享给大家供大家参考。具体如下: #!/usr/bin/env python #encoding:utf8 d...

本文实例讲述了Python字符串匹配算法KMP。分享给大家供大家参考。具体如下:

#!/usr/bin/env python
#encoding:utf8
def next(pattern):
p_len = len(pattern)
pos = [-1]*p_len
j = -1
for i in range(1, p_len):
while j > -1 and pattern[j+1] != pattern[i]:
j = pos[j]
if pattern[j+1] == pattern[i]:
j = j + 1
pos[i] = j
return pos
def kmp(ss, pattern):
pos = next(pattern)
ss_len = len(ss)
pattern_len = len(pattern)
j = -1
for i in range(ss_len):
while j > -1 and pattern[j+1] != ss[i]:
j = pos[j]
if pattern[j+1] == ss[i]:
j = j + 1
if j == pattern_len-1:
print 'matched @: %s' % str(i-pattern_len+1)
j = pos[j]
kmp(u'上海自来水来自海上海', u'上海')

希望本文所述对大家的Python程序设计有所帮助。

上一篇:

下一篇: