#include <iostream>
using namespace std;

#include <boost/preprocessor/slot/counter.hpp>

constexpr int A  = BOOST_PP_COUNTER; // 0

#include BOOST_PP_UPDATE_COUNTER()

constexpr int B = BOOST_PP_COUNTER; // 1

#include BOOST_PP_UPDATE_COUNTER()

constexpr int C = BOOST_PP_COUNTER; // 2

#include BOOST_PP_UPDATE_COUNTER()

constexpr int D = BOOST_PP_COUNTER; // 3


int main() {
	cout << A << B << C << D << endl;
}