字符串匹配常用算法
1 暴力匹配
思想:逐一匹配
时间复杂度:
实现:
# -----------------------------------------
# https://www.geeksforgeeks.org/naive-algorithm-for-pattern-searching/?ref=lbp
def find_brute_force(pat, txt):
"""在txt中找到pat的匹配项,并返回txt匹配时第一个索引"""
m, n = len(pat), len(txt)
for begin in range(n - m + 1):
match = 0
while match < m:
if txt[begin + match] != pat[match]:
break
match += 1
if match =