Remove duplicate elements from Array.cpp

//{ Driver Code Starts
//Initial template for C++

#include <bits/stdc++.h>
using namespace std;


// } Driver Code Ends
//User function template for C++

class Solution{
public:
    int remove_duplicate(int a[],int n){
        // code here
        set<int>s;
    for(int i =0; i < n; i++)
        s.insert(a[i]);
        
    int i=0;
    set<int> ::iterator itr;
    for(itr= s.begin(); itr != s.end(); itr++)
    {
        a[i] = *itr;
        i++;
    }
    return i; 
    }
};

//{ Driver Code Starts.
int main()
{
    int T;
    cin>>T;
    while(T--)
    {
        int N;
        cin>>N;
        int a[N];
        for(int i=0;i<N;i++)
        {
            cin>>a[i];
        }
    Solution ob;
    int n = ob.remove_duplicate(a,N);

    for(int i=0;i<n;i++)
        cout<<a[i]<<" ";
    cout<<endl;
    }
}
// } Driver Code Ends