---
id: 6
title: String Compression and Decompression
topics: [string]
difficulty: easy
---

## Question

```
'''
Given a string, compress it by grouping repeated characters. The length after
compression must always be smaller than or equal to the original string.

'aaabbccc' => 'a3b2c3'
'''
```

```
'''
Given the above compressed string, decompress to obtain the original string.

'a3b2c3' => 'aaabbccc'
'''
```