#include <stdio.h>

#define JOIN(a, b) (a ## b)
// WARNING: don't LOOP in the same line
#define LOOP(n) for (unsigned JOIN(HIDDEN, __LINE__) = 0; JOIN(HIDDEN, __LINE__) < n; JOIN(HIDDEN, __LINE__)++)

int main(void) {
	LOOP(4) {
		printf("foo");
		LOOP(2) printf(" bar");
		puts("");
	}
	return 0;
}