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TODO 0097. Interleaving String   medium

Given strings s1, s2, and s3, find whether s3 is formed by an interleaving of s1 and s2.

An interleaving of two strings s and t is a configuration where s and t are divided into n and m substrings respectively, such that:

  • s = s_{1} + s_{2} + ... + s_{n}
  • t = t_{1} + t_{2} + ... + t_{m}
  • |n - m| <= 1
  • The interleaving is s_{1} + t_{1} + s_{2} + t_{2} + s_{3} + t_{3} + ... or t_{1} + s_{1} + t_{2} + s_{2} + t_{3} + s_{3} + ...

Note: a + b is the concatenation of strings a and b.

Example 1:

Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"
Output: true
Explanation: One way to obtain s3 is:
Split s1 into s1 = "aa" + "bc" + "c", and s2 into s2 = "dbbc" + "a".
Interleaving the two splits, we get "aa" + "dbbc" + "bc" + "a" + "c" = "aadbbcbcac".
Since s3 can be obtained by interleaving s1 and s2, we return true.

Example 2:

Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc"
Output: false
Explanation: Notice how it is impossible to interleave s2 with any other string to obtain s3.

Example 3:

Input: s1 = "", s2 = "", s3 = ""
Output: true

Constraints:

  • 0 <= s1.length, s2.length <= 100
  • 0 <= s3.length <= 200
  • s1, s2, and s3 consist of lowercase English letters.

Follow up: Could you solve it using only O(s2.length) additional memory space?

TODO Approach

Write your approach here.

TODO Python

class Solution:
    def isInterleave(self, s1: str, s2: str, s3: str) -> bool:

TODO C++

class Solution {
public:
    bool isInterleave(string s1, string s2, string s3) {
        
    }
};