#include <iostream>
#include <vector>
using namespace std;
int main()
{
    cout << "Please enter the length of the array: ";
    int i;
    cin >> i;
    vector<int> v(i);

    for(size_t j=0; j < v.size(); ++j)
    {
        v[j] = 2*j;
        cout << v[j] << ' ' ;
    }
    cout << '\n';
}