Solving Regular Expression Matching in Javascript. Please try yourself first to solve the problem and submit your implementation to LeetCode before looking into solution.

## Problem Description

Given an input string (s) and a pattern (p), implement regular expression matching with support for '.' and '*'.

• '.' Matches any single character.
• '*' Matches zero or more of the preceding element.
• The matching should cover the entire input string (not partial).

Note:

• s could be empty and contains only lowercase letters a-z.
• p could be empty and contains only lowercase letters a-z, and characters like . or *.

Example 1:

```Input:
s = "aa"
p = "a"

Output: false
```

Explanation: "a" does not match the entire string "aa".

Example 2:

```Input:

s = "aa"
p = "a*"
Output: true
```

Explanation: '*' means zero or more of the precedeng element, 'a'. Therefore, by repeating 'a' once, it becomes "aa".

Example 3:

```Input:
s = "ab"
p = ".*"
Output: true
```

Explanation: "." means "zero or more () of any character (.)".

Example 4:

```Input:
s = "aab"
p = "cab"
Output: true
```

Explanation: c can be repeated 0 times, a can be repeated 1 time. Therefore it matches "aab".

Example 5:

```Input:
s = "mississippi"
p = "misisp*."
Output: false
```

See the full details of the problem Regular Expression Matching at LeetCode

Originally posted at: @github.com/ignacio-chiazzo/Algorithms-Leetcode-Javascript