// b.cpp
int global_b = 7
// main.cpp
extern int global_b;
int main() {
std::cout << global_b; // 输出是多少
return 0;
}
// b.cpp
int global_b = 7
// main.cpp
extern int global_b;
int main() {
std::cout << global_b; // 输出是多少
return 0;
}