Merge 2 Sorted Arrays

#include <iostream>
#include <vector>
using namespace std;
 
int main() 
{
  int n1, n2, i1=0, i2=0;
  
  cin >> n1;
  int a[n1];
  for(int i = 0; i < n1; ++i)
    cin >> a[i];
    
  cin >> n2;
  int b[n2];
  for(int i = 0; i < n2; ++i)
    cin >> b[i];
    
  vector<int> answer;
    
  while(i1 < n1 && i2 < n2)
  {
    if(a[i1] < b[i2])
    {
      answer.push_back(a[i1]);
      ++i1;
    }
    else if(a[i1] > b[i2])
    {
      answer.push_back(b[i2]);
      ++i2;
    }
  }
  
  while(i1 < n1)
  {
    answer.push_back(a[i1]);
    ++i1;
  }
  
  while(i2 < n2)
  {
    answer.push_back(b[i2]);
    ++i2;
  }
  
  for(int num : answer)
    cout << num << " ";
  
  return 0;
}