FIND THE PAIR IN AN ARRAY FOR A GIVEN SUM

Hii friends,this method is simple brute force i think when interviewer asks you this questions then this solution must come in your mind then u can optimise this So right now i am just posting this brute force solution later i will upload its optimize version. Optimized Version

#include<bits/stdc++.h>
using namespace std;
int main(){

  int n,i,j;
  cout << "Enter the size of array:\n";
  cin >> n;
  int arr[n];

  cout << "Enter the elements of array:\n";
  for(i=0;i<n;i++){
   cin >> arr[i];
  }

  int sum;
  cout << "Enter the value of sum:\n";
  cin>> sum;

  for(i=0;i<n;i++){
   for(j=i+1;j<n;j++){
    if((arr[i]+arr[j])==sum){
     cout << arr[i] << " " << arr[j] << endl;
    }
   }
  }




 return 0;
}