Answer Happy

int main () {
int x = 4;
if (fork() == 0)
printf("printf1: x=%d\n", ++x);
printf("printf2: x=%d\n", --x);
exit 0;
}
Solution (may be hand-drawn):
int main () {
fork();
printf("hello\n");
fork();
printf("world\n");
exit 0;
}
Solution (may be hand-drawn):