Question

Would someone help me custom or implementing methods Iterator insert(Iterator position, const int &data) and Iterator erase(Iterator position) in class vector c++. Thank you very much.

Answer 1

//Inserting into the vector

#include <iostream>
#include <vector>

using namespace std;

int main()
{
   vector<int> sample_vector(3,100);
   vector<int>::iterator it;
  
   cout << "Initially sample_vector contains:";
for (it=sample_vector.begin(); it<sample_vector.end(); it++)
cout << ' ' << *it;
cout <<endl;
  
   it = sample_vector.begin();
   it = sample_vector.insert ( it , 200 ); //insert at the 1st position
  
   sample_vector.insert(it+1,400); //inserting at the second position
  
cout << "After insertion sample_vector contains:";
for (it=sample_vector.begin(); it<sample_vector.end(); it++)
cout << ' ' << *it;
cout <<endl;
  
return 0;
}

OUTPUT:

//Erasing from the vector

#include <iostream>
#include <vector>

using namespace std;

int main ()
{
vector<int> sample_vector;

// setting values (from 1 to 10) inside the vector
for (int i=1; i<=10; i++)
   sample_vector.push_back(i);
cout << "Initially sample_vector contains:";
for (unsigned i=0; i<sample_vector.size(); ++i)
cout << ' ' << sample_vector[i];
cout <<endl;

// erasing the 4th element
sample_vector.erase (sample_vector.begin()+3);
  
cout << "After erasing sample_vector contains:";
for (unsigned i=0; i<sample_vector.size(); ++i)
cout << ' ' << sample_vector[i];
cout <<endl;

}

OUTPUT: