C++ miscellaneous
practice.

#include <iostream>
#include <string>
#include <cstdlib>
using namespace std;
template<class T, class U = char>
class A
{
	T a;
	U b;
    public:
	A(T a_val, char b_val = '$'){
		this->a = a_val;
		this->b = b_val;
	}
	void print(){
		cout<<a<<' '<<b<<endl;
	}
};
 
int main(int argc, char const *argv[])
{
	A <int, int> a1(5,10);
	A <int> a2(5);
	A <float> a3(10.0);
	return 0;
}

#include<iostream>
#include<any>
using namespace std;
int main()
{
	float val = 5.5;
	any var(val);
	if(var.has_value())
        {
            cout<<"Var is not Empty\n";
        }
        else
        {
            cout<<"Var is Empty\n";
        }
	return 0;
}

#include<iostream>
using namespace std;
class Add
{
	int x;
   public:
	Add(int x){
		this->x = x;
	}
	int operator()(int a){
		return x+a;
	}
};
int main()
{
	Add add_5(5);
	int a = 5;
	cout<<add_5(a);
	return 0;
}

#include <iostream>
using namespace std;
int main(void)
{
    const char *one = "Test";
    cout << one << endl;
    const char *two = one;
    cout << two << endl;
    return 0;
}