#include <iostream>

template< int C, typename T, typename U > struct selector;
template< typename T, typename U > struct selector<1, T, U> : T {};
template< typename T, typename U > struct selector<0, T, U> : U {};

template< int N > struct node : selector< N%2, node<3*N+1>, node<N/2> >
{
        ~node() { std::cout << N << ","; }
};
template<> struct node<1>
{
        ~node() { std::cout << "1\n"; }
};

node<22> lst;
int main() {}

#include <iostream>

template< int N > struct node : node<(N%2)*(3*N+1)+(1-N%2)*(N/2)>
{
        ~node() { std::cout << N << ","; }
};
template<> struct node<1>
{
        ~node() { std::cout << "1\n"; }
};

node<22> lst;