1-2 构造函数

题目

Create a class without any constructors, and show that you can create objects with the default constructor. Now create a nondefault constructor (one with an argument) for the class, and try compiling again. Explain what happened.

代码

#include<iostream>
using namespace std;
class A 
{
	public:
		A(int X=0){x=X+1;}
		void show(){cout << x<<endl;}
	private:
		int x;
};
int main()
{
	A test(5);
	cout<< "x = " ;
	test.show();
	cout << endl;
	
	return 0;
}

结果