判断是不是闰年

闰年计算方法：

1. 能被400整除。
2. 能被4整除，不能被100整除。

#include<iostream>
using namespace std;

class Sample
{
private:
	int x;
public:
	Sample() {}
	Sample(int a) {x=a;}
	void disp() {cout << "x=" << x << endl;}
	friend Sample operator*(Sample &s1, Sample &s2);
	void LeapYear()
	{
		if(x%400 == 0||(x%4==0 && x%100 != 0))
			cout << x << "是闰年" << endl;
		else
			cout << x << "不是闰年" << endl;
	}
};

Sample operator*(Sample &s1, Sample &s2) {return Sample(s1.x * s2.x);}

void main()
{
	Sample obj1(30);
	Sample obj2(101);
	Sample obj3;
	obj3 = obj1 * obj2;
	obj3.disp();
	obj3.LeapYear();
}

结果：