// expect: 1/2/3/4/
include rt;
void pn(int x) { rt.put_n(x); rt.put_c(10); }
fn main() {
	int _a = 1, a1_b2 = 2, A = 3, a = 4;
	pn(_a); pn(a1_b2); pn(A); pn(a);
	return 0;
}