Python - KMP算法

def kmp_match(tex, pat):
	n = len(tex)
	m = len(pat)
	tex = '0' + tex
	pat = '0' + pat
	pi = []
	pi.append(0)
	pi.append(0)
	p = 0
	for i in range(2, m + 1):
		while (p) and (pat[p + 1] != pat[i]):
			p = pi[p]
		if (pat[p + 1] == pat[i]):
			p = p + 1
		pi.append(p)
	p = 0
	for i in range(1, n + 1):
		while (p) and (pat[p + 1] != tex[i]):
			p = pi[p]
		if (pat[p + 1] == tex[i]):
			p = p + 1
		if (p == m):
			print i - m + 1
			p = pi[p]

tex = 'abbababbabbaaabaabb'
pat = 'aab'
kmp_match(tex, pat)