Question

For example, I good 2 vector, say vector current, vector to_delete. Is there some good way to delete elements which appear both in current.

Here is my way to do it. I guess it not looks good. So please help me out. Thank you.

#include <iostream>
#include <vector>
using namespace std;
int main(){
  vector <double> current;
  current.push_back(1.1);
  current.push_back(2.1); 
  current.push_back(3.1); 
  current.push_back(4.1); 
  current.push_back(5.1); 
  current.push_back(6.1); 
  current.push_back(7.1); 
  current.push_back(8.1);
  vector <double> to_delete;
  to_delete.push_back(2.1);
  to_delete.push_back(5.1);
  for(int i = 0;i<to_delete.size();i++){
    int loc = -1;
    for(int j = 0; j < current.size();j++)
    {
      if(current[j]==to_delete[i]){
        loc = j;
        break;
      }
    }
    if(loc >= 0){
      current.erase(current.begin()+loc);
    }
  }

  for(int i = 0;i < current.size();i++){
    cout << current[i]<< endl;
  }
}

Answer 1

You could use std::find() instead of a manual loop to find the position of the element that should be deleted.

std::vector<double>::iterator del =
      std::find(current.begin(), current.end(), to_delete[i]);
if (del != current.end())
    current.erase(del);