Distinct Difference

class Solution {
  public:
vector<int> getDistinctDifference(int N, vector<int> &A) 
{
        // code here
     vector<int>distLeft(A.size(),0);
     vector<int>distRight(A.size(),0);
     set<int>distElementsSet;
     vector<int>ans;
      
     distLeft[0]=0;
     distRight[A.size()-1]=0;
     distElementsSet.insert(A[0]);
        
     //left traversal distinct elements count
    for(int i=1;i<A.size();i++)
    {
        distLeft[i] += distElementsSet.size();
        distElementsSet.insert(A[i]);
   }
        
    distElementsSet = set<int>(); //re-initialize set
    distElementsSet.insert(A[A.size()-1]);
     //right traversal distinct elements count
    for(int i=A.size()-2;i>=0;i--)
    {
      distRight[i] += distElementsSet.size();
      distElementsSet.insert(A[i]);
    }
    for(int i=0;i<A.size();i++)
   {
      ans.push_back(distLeft[i] - distRight[i]);
   }
        return ans;
 }
};