Program to partition two strings such that each partition forms anagram in Python

Suppose we have two non-empty strings s and t that are of the same length. We have to partition them into substrings such that each pair of s and t substring is the same size and they are the anagrams of each other. Now find the cut indexes such that it results in the maximum number of cuts of s and t. If no result is found, then return empty list.

So, if the input is like s = "bowcattiger" t = "owbactietgr", then the output will be [0, 3, 5, 6, 10], as we can partition the string into 5 partitions such that each string is an anagram of each other. s = ["bow", "ca", "t", "tige", "r"], t = ["owb", "ac", "t", "ietg", "r"]

To solve this, we will follow these steps −

• intervals := a new list
• cs := a map with character present in s and its frequency
• ct := a map with character present in t and its frequency
• if cs is not same as ct, then
  • return a new list
• for x in range size of s - 1 down to 0, do
  • cs[s[x]] := cs[s[x]] - 1
  • ct[t[x]] := ct[t[x]] - 1
  • if cs is same as ct, then
    • insert x at the end of intervals
• sort the list intervals and return

Let us see the following implementation to get better understanding −

Example

 Live Demo

from collections import Counter class Solution:    def solve(self, a, b):       intervals = []       ca = Counter(a)       cb = Counter(b)       if ca != cb:          return []       for x in reversed(range(len(a))):             ca[a[x]] -= 1             cb[b[x]] -= 1             if ca == cb:                intervals.append(x)       return sorted(intervals) ob = Solution() s = "bowcattiger" t = "owbactietgr" print(ob.solve(s, t))

Input

"bowcattiger", "owbactietgr"

Output

[0, 3, 5, 6, 10]