What will be the output of the program?

#include <iostream>
using namespace std;
class A {
public:
    A() { cout << "A"; }
    ~A() { cout << "~A"; }
};
class B : public A {
public:
    B() { cout << "B"; }
    ~B() { cout << "~B"; }
};
int main() {
    { B b; }
    cout << endl;
    return 0;
}