Q. What is the output of the following C++ code?

#include<iostream>
using namespace std;

class A {
private:
int val;
public:
A(int v = 0) : val(v) {}
void display() { cout << "val = " << val << endl;}
};

class B {
private:
int val;
public:
B(int v) : val(v) {}
operator A() const { return A(val); }
};

void f(A a)
{ a.display(); }

int main() {
B b(5);
f(b);
f(55);
return 0;
}