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# Problem Challenge 2: Find the Smallest Missing Positive Number (medium)

## Problem Statement

Given an unsorted array containing numbers, find the **smallest missing positive number** in it.

**Note**: Positive numbers start from '1'.

**Example 1**:

```
Input: [-3, 1, 5, 4, 2]
Output: 3
Explanation: The smallest missing positive number is '3'
```

**Example 2**:

```
Input: [3, -2, 0, 1, 2]
Output: 4
```

**Example 3**:

```
Input: [3, 2, 5, 1]
Output: 4
```

**Example 4**:

```
Input: [33, 37, 5]
Output: 1
```

**Constraints:**

- 1 <= nums.length <= 10^5
- -2<sup>31</sup> <= nums[i] <= 2<sup>31</sup> - 1

## Try it yourself

Try solving this question here:

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