# 0459. Repeated Substring Pattern

https://leetcode.com/problems/repeated-substring-pattern

## Description

Given a string `s`, check if it can be constructed by taking a substring of it and appending multiple copies of the substring together.

**Example 1:**

```
**Input:** s = "abab"
**Output:** true
**Explanation:** It is the substring "ab" twice.
```

**Example 2:**

```
**Input:** s = "aba"
**Output:** false
```

**Example 3:**

```
**Input:** s = "abcabcabcabc"
**Output:** true
**Explanation:** It is the substring "abc" four times or the substring "abcabc" twice.
```

**Constraints:**

* `1 <= s.length <= 104`
* `s` consists of lowercase English letters.

## ac

```java
```
