WeekB.cpp

#include "stdafx.h"
#include <iostream>

using namespace std;

bool IsCorrect(int y,int m,int d);

int getResult(int y,int m,int d);

int maxA[12]={31,28,31,30,31,30,31,31,30,31,30,31};

void main()
{
	int year, month, day;
	while(1)
	{
		cout<<"请输入日期(yy/mm/dd)：";
		cin>>year;
		cin.ignore(1,'/');
		cin>>month;
		cin.ignore(1,'/');
		cin>>day;
		bool valid=IsCorrect(year,month,day);
		while(!valid)
		{
			cout<<"输入错误，请重新输入(yy/mm/dd):";
			cin>>year;
			cin.ignore(1,'/');
			cin>>month;
			cin.ignore(1,'/');
			cin>>day;
			valid=IsCorrect(year,month,day);
		}
		maxA[1]=28;
		int result=getResult(year,month,day);
		cout<<year<<"年"<<month<<"月"<<day<<"日是星期";
		switch(result)
		{
		case 0:
			cout<<"一!\n";
			break;
		case 1:
			cout<<"二!\n";
			break;
		case 2:
			cout<<"三!\n";
			break;
		case 3:
			cout<<"四!\n";
			break;
		case 4:
			cout<<"五!\n";
			break;
		case 5:
			cout<<"六!\n";
			break;
		case 6:
			cout<<"日!\n";
			break;
		default:
			cout<<"计算出现错误!\n";
			break;
		}
		cout<<endl<<endl;
	}
}
bool IsCorrect(int y,int m,int d)
{
	if(y<1)
		return false;
	else
	{
		if(((y%4==0)&&(y%100!=0))||(y%400==0))
			maxA[1]=29;
		if(m<0||m>12)
			return false;
		else
		{
			if(d>maxA[m-1])
				return false;
			else
				return true;
		}
	}
}
int getResult(int y,int m,int d)
{
	long totalDays=0;
	for(int i=1;i<y;i++)
	{
		if(((i%4==0)&&(i%100!=0))||(i%400==0))
			totalDays+=366;
		else
			totalDays+=365;
	}
	if(((y%4==0)&&(y%100!=0))||(y%400==0))
		maxA[1]=29;
	else
		maxA[1]=28;
	for(int i=1;i<m;i++)
	{
		totalDays+=maxA[i-1];
	}
	totalDays+=(d-1);
	maxA[1]=28;
	return (totalDays%7);
}