初学C++之——switch语句

switch语句也叫开关语句，类似于当你面对多条路时，选择走那条的问题

示例：依次输入年、月、日，输出这天是星期几

#include<iostream>
using namespace std;
void PrintfDay(int y, int m, int d); //声明PrintfDay函数  

void CaculateWeekDay(int y, int m, int d)
{
	if (m == 1 || m == 2) //把一月和二月换算成上一年的十三月和是四月  
	{
		m += 12;
		y--;
	}
	int Week = (d + 2 * m + 3 * (m + 1) / 5 + y + y / 4 - y / 100 + y / 400) % 7;
	switch (Week)
	{
	case 0: PrintfDay(y, m, d); cout << "是星期一" << endl; break;
	case 1: PrintfDay(y, m, d); cout << "是星期二" << endl; break;
	case 2: PrintfDay(y, m, d); cout << "是星期三" << endl; break;
	case 3: PrintfDay(y, m, d); cout << "是星期四" << endl; break;
	case 4: PrintfDay(y, m, d); cout << "是星期五" << endl; break;
	case 5: PrintfDay(y, m, d); cout << "是星期六" << endl; break;
	case 6: PrintfDay(y, m, d); cout << "是星期日" << endl; break;
	}
}

void PrintfDay(int y, int m, int d)
{
	cout << y << "年" << m << "月" << d << "日";
}
int main()
{
	int year, month, day;
	cout << "请输入年 月 日" << endl;
	cin >> year >> month >> day;
	CaculateWeekDay(year, month, day);
	return 0;
}

运行结果如下：