RemoveDuplicates.cpp

// C++ program to remove duplicates in-place
#include<bits/stdc++.h>
using namespace std;
// Function to remove duplicate elements This function returns new size of modified array.
int removeDuplicates(int arr[], int n)
{
	if (n == 0 || n == 1)
		return n;
	// To store index of next unique element
	int j = 0;
	// Doing same as done in Method 1
	// Just maintaining another updated index i.e. j
	for (int i = 0; i < n - 1; i++)
		if (arr[i] != arr[i + 1])
			arr[j++] = arr[i];

	arr[j++] = arr[n - 1];
	return j;
}
// Main Function code
int main()
{
	int arr[] = {1, 3, 3, 4, 4, 5,6 , 6, 6};
	int n = sizeof(arr) / sizeof(arr[0]);
	// removeDuplicates() returns new size of array.
	n = removeDuplicates(arr, n);
	// Print updated array
	for (int i = 0; i < n; i++)
		cout << arr[i] << " ";
	return 0;
}