//file a

struct A bb;

int
main() {
   bb.b=5;
   bb.c=10;

   show();
}


//file b

extern struct A bb;

int
show() {
        int d;
        int e;

        d = bb.b + 10;
        e = bb.c + 10;

        printf("d = %d \n",d);
        printf("e = %d \n",e);
}