#include <stdio.h>

void mary() {
	printf( "MARY\n" );
}

#define FIB_INIT { 0 }
typedef struct { int next; int fn1, fn2; } Fib;
int fib( Fib * f ) {
	static void * states[] = { &&s1, &&s2, &&s3 };
	goto *states[f->next];
  s1:
	mary();
	f->fn1 = 0;
	f->next = 1;
	return f->fn1;
  s2:
	mary();
	f->fn2 = f->fn1;
	f->fn1 = 1;
	f->next = 2;
	return f->fn1;
  s3:;
	mary();
	int fn = f->fn1 + f->fn2;
	f->fn2 = f->fn1;
	f->fn1 = fn;
	return fn;
}
int main() {
	Fib f1 = FIB_INIT, f2 = FIB_INIT;
	for ( int i = 0; i < 10; i += 1 ) {
		printf( "%d %d\n", fib( &f1 ), fib( &f2 ) );
	}
}

// Local Variables: //
// tab-width: 4 //
// compile-command: "gcc Fib2.c" //
// End: //