Remove duplicates from a sorted array using STL in C++

Given a sorted array, the task is to remove the duplicate elements from the array using STL in C++

Examples:

```Input: arr[] = {2, 2, 2, 2, 2}
Output: arr[] = {2}

Input: arr[] = {1, 2, 2, 3, 4, 4, 4, 5, 5}
Output: arr[] = {1, 2, 3, 4, 5}
```

Approach:
The duplicates of the array can be removed using the unique() function provided in STL.

Below is the implementation of the above approach.

 `#include ` `using` `namespace` `std; ` ` `  `// Function to remove duplicate elements ` `void` `removeDuplicates(``int` `arr[], ``int` `n) ` `{ ` ` `  `    ``// Initialise a vector ` `    ``// to store the array values ` `    ``// and an iterator ` `    ``// to traverse this vector ` `    ``vector<``int``> v(arr, arr + n); ` `    ``vector<``int``>::iterator it; ` ` `  `    ``// using unique() method to remove duplicates ` `    ``it = unique(v.begin(), v.end()); ` ` `  `    ``// resize the new vector ` `    ``v.resize(distance(v.begin(), it)); ` ` `  `    ``// Print the array with duplicates removed ` `    ``cout << ``"\nAfter removing duplicates:\n"``; ` `    ``for` `(it = v.begin(); it != v.end(); ++it) ` `        ``cout << *it << ``", "``; ` `    ``cout << ``'\n'``; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``int` `arr[] = { 1, 2, 2, 3, 4, 4, 4, 5, 5 }; ` ` `  `    ``int` `n = ``sizeof``(arr) / ``sizeof``(arr[0]); ` ` `  `    ``// Print array ` `    ``cout << ``"\nBefore removing duplicates:\n"``; ` `    ``for` `(``int` `i = 0; i < n; i++) ` `        ``cout << arr[i] << ``" "``; ` ` `  `    ``// call removeDuplicates() ` `    ``removeDuplicates(arr, n); ` ` `  `    ``return` `0; ` `} `

Output:

```Before removing duplicates:
1 2 2 3 4 4 4 5 5
After removing duplicates:
1, 2, 3, 4, 5,
```

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