萌新C++求大佬们解惑（舅舅孩子）

Question

#include<iostream>
using namespace std;

class Cylinder 
{
	private:
		float radius;
		float high;
		double volume;
	public:
		Cylinder();
		double CalculateV();
		void OutPut();
}; 

Cylinder::Cylinder()
{
	float aradius,ahigh;
	cin >> aradius >> ahigh;
	radius = aradius;
	high = ahigh;
}

double Cylinder::CalculateV()
{
	volume = 3.14*radius*high;
}

void Cylinder::OutPut()
{
	cout << "The volume of the cylinder is:" << volume;
}

int main()
{
	Cylinder cylinder1;
	Cylinder();
	cylinder1.CalculateV();
	cylinder1.OutPut();
}

各位大佬我想问一下，我这里为什么会要输入四个变量呢，我明明只定义了aradius和ahigh啊

Answer 1

你用Cylinder cylinder1的时候，它自动调用构造函数要求你输入一次了，后面你又自己调用Cylinder()，所以又要输入一次

你后面单独的调用Cylinder，对cylinder.radius和cylinder.high的值不影响