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Dutch National Flag Problem (medium)

## Problem Statement

Given an array containing 0s, 1s and 2s, sort the array in-place. You should treat numbers of the array as objects, hence, we can’t count 0s, 1s, and 2s to recreate the array.

The flag of the Netherlands consists of three colors: red, white and blue; and since our input array also consists of three different numbers that is why it is called **Dutch National Flag problem**.

**Example 1**:

```
Input: [1, 0, 2, 1, 0]
Output: [0 0 1 1 2]
```

**Example 2**:

```
Input: [2, 2, 0, 1, 2, 0]
Output: [0 0 1 2 2 2 ]
```

**Constraints:**

`n == arr.length`

`1 <= n <= 300`

`arr[i] is either 0, 1, or 2.`

## Try it yourself

Try solving this question here:

Python3

Python3

. . .

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