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# 217. Contains Duplicate

## Easy

***

Given an integer array `nums`, return `true` if any value appears **at least twice** in the array, and return `false` if every element is distinct.

 

**Example 1:**

```
Input: nums = [1,2,3,1]
Output: true
```

**Example 2:**

```
Input: nums = [1,2,3,4]
Output: false
```

**Example 3:**

```
Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true
```

 

**Constraints:**

* `1 <= nums.length <= 105`
* `-109 <= nums[i] <= 109`