#include <iostream>
#include <functional>

void function(int& number)
{
	number = 50;
}

using functionType = void(*)(int&);

int main()
{
	//case 1:
	int n1 = 10;
	auto f1 = std::bind(function, 10);
	f1();
	std::cout<<n1<<std::endl; //  : 10.
	
	//case 2:
	int n2 = 20;
	auto f2 = std::bind(function, std::ref(n2));
	f2();
	std::cout<<n2<<std::endl; //  : 50. 
	
	//case 3:
	int n3 = 30;
	auto f3 = std::bind(function, n3);
	f3();
	std::cout<< n3 <<std::endl; //  : 30 
	
	
	return 0;
}