Virtual Destructors

Lab C++ Advanced 30 points

Write class Base with a virtual destructor printing ~Base, and Derived whose destructor prints ~Derived NAME. For each name, create a Derived through a unique_ptr<Base>, print made NAME, then reset it.

Input

n, then n names.

Output

The event trace.

Example

Input

2
A
B

Output

made A
~Derived A
~Base
made B
~Derived B
~Base

Sample input available Sample output available

Editor

C++

Hints

Without virtual, deleting through a Base pointer would skip ~Derived.

Solution explanation

Destructors run from the most derived class up to the base.

Show solution

#include <iostream>
#include <memory>
#include <string>
using namespace std;

class Base {
public:
    virtual ~Base() { cout << "~Base\n"; }
};

class Derived : public Base {
public:
    explicit Derived(string name) : name_(name) {}
    ~Derived() override { cout << "~Derived " << name_ << "\n"; }

private:
    string name_;
};

int main() {
    int n;
    cin >> n;
    for (int i = 0; i < n; i++) {
        string name;
        cin >> name;
        unique_ptr<Base> p = make_unique<Derived>(name);
        cout << "made " << name << "\n";
        p.reset();
    }
    return 0;
}

Output

Answer