I’d like to compare 2 strings and keep the matched, splitting off where the comparison fails.
So if I have 2 strings –
string1 = apples string2 = appleses answer = apples
Another example, as the string could have more than one word.
string1 = apple pie available string2 = apple pies answer = apple pie
I’m sure there is a simple Python way of doing this but I can’t work it out, any help and explanation appreciated.
Its called Longest Common Substring problem. Here I present a simple, easy to understand but inefficient solution. It will take a long time to produce correct output for large strings, as the complexity of this algorithm is O(N^2).
def longestSubstringFinder(string1, string2): answer = "" len1, len2 = len(string1), len(string2) for i in range(len1): match = "" for j in range(len2): if (i + j < len1 and string1[i + j] == string2[j]): match += string2[j] else: if (len(match) > len(answer)): answer = match match = "" return answer print longestSubstringFinder("apple pie available", "apple pies") print longestSubstringFinder("apples", "appleses") print longestSubstringFinder("bapples", "cappleses")
apple pie apples apples
Answered By – thefourtheye
Answer Checked By – Candace Johnson (BugsFixing Volunteer)