/* $begin forkprob7 */
#include "csapp.h"
int counter = 1;

int main() 
{
    if (fork() == 0) {
	counter--;  
	exit(0);
    }
    else {
	Wait(NULL); 
	printf("counter = %d\n", ++counter);
    }
    exit(0);
}
/* $end forkprob7 */