# Challenge: Longest Common Substring

Let's write some code to find the longest common substring.

## We'll cover the following

## Problem statement

Given two strings, `s1`

and `s2`

, write a function that finds and returns the length of the longest substring of `s2`

and `s1`

(if any exist).

### Input

Two strings.

### Output

An integer.

### Sample input

```
string1 = "www.educative.io/explore";
string2 = "educative.io/edpresso";
```

### Sample output

```
14
```

## Coding exercise

Take a close look and design a step-by-step algorithm before jumping to the implementation. This problem is designed for your practice, so try to solve it on your own first. If you get stuck, you can always refer to the hint and solution provided in the code tab. Good Luck!

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