Python中的SequenceMatcher，用于最长公共子串。
给定两个字符串，我们的任务是打印最长的公共子字符串。我们将使用SequenceMatcher.find_longest_match()方法解决python中的问题。
difflib.SequenceMatcher类是用于比较任何类型的序列对的灵活类，只要序列元素是可哈希的即可。
find_longest_match(a,x,b,y)
在a[a：x]和b[b：y]中找到最长的匹配块。
例子
Input: str1 = "pythonprogramming",
str2 = "pro"
Output: pro算法
Step 1: Enter two string. Step 2: initialize SequenceMatcher object with the input string. Step 3: find the match of longest sub-string output. Step 4: print longest substring.
范例程式码
# Python program to find Longest Common Sub-string
from difflib import SequenceMatcher
def matchsubstring(m,n):
seqMatch = SequenceMatcher(None,m,n)
match = seqMatch.find_longest_match(0, len(m), 0, len(n))
if (match.size!=0):
print ("Common Substring ::>",m[match.a: match.a + match.size])
else:
print ('No longest common sub-string found')
# Driver program
if __name__ == "__main__":
X = input("Enter first String ")
Y = input("Enter second String ")
matchsubstring(X,Y)输出结果
Enter first String pythonprogramming Enter second String pro Common Substring ::> pro