# 0097. Interleaving String

<https://leetcode.com/problems/interleaving-string>

## Description

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 they are divided into **non-empty** substrings such that:

* `s = s1 + s2 + ... + sn`
* `t = t1 + t2 + ... + tm`
* `|n - m| <= 1`
* The **interleaving** is `s1 + t1 + s2 + t2 + s3 + t3 + ...` or `t1 + s1 + t2 + s2 + t3 + s3 + ...`

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

**Example 1:**

![](https://assets.leetcode.com/uploads/2020/09/02/interleave.jpg)

```
**Input:** s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"
**Output:** true
```

**Example 2:**

```
**Input:** s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc"
**Output:** false
```

**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?

## ac

```java
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://jaywin.gitbook.io/leetcode/solutions/0097-interleaving-string.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.