题目描述:求一个字符串的最长回文子串
def maxhuiwen(s):
k=len(s)
martix=[[0 for i in range(k)] for j in range(k)]
len1=0
substr=""
for j in range(k):
for i in range(0,j+1):
if j-i<=1:
if s[i]==s[j]:
martix[i][j]=1
if len1<j-i+1:
len1=j-i+1
substr=s[i:j+1]
else:
if s[i] == s[j] and martix[i+1][j-1]:
martix[i][j] = 1
if len1 < j - i + 1:
len1 = j - i + 1
substr = s[i:j + 1]
return substr