#include <iostream>
using namespace std;
int main()
{

    int a;
    for (int j = 0; j < 3; j++)
    {
        do
        {
            cin >> a;

        } while (a < 0);
    }
    int counter = 1;
    while (a >= counter)
    {
        cout << " " << counter;
        counter++;
    }
    return 0;
}