#include<stdio.h>

int counter(){
// Re-used on each function call
	static int c = 0;
	return c++;
}

int main(){
	printf("counter returned:  %d\n", counter());
	printf("counter returned:  %d\n", counter());
	printf("counter returned:  %d\n", counter());
	printf("counter returned:  %d\n", counter());
	printf("counter returned:  %d\n", counter());
	return 0;
}