4.1.1 A

Description

A calendar is a system for measuring time, from hours and minutes, to months and days, and finally to years and centuries. The terms of hour, day, month, year and century are all units of time measurements of a calender system.
According to the Gregorian calendar, which is the civil calendar in use today, years evenly divisible by 4 are leap years, with the exception of centurial years that are not evenly divisible by 400. Therefore, the years 1700, 1800, 1900 and 2100 are not leap years, but 1600, 2000, and 2400 are leap years.
Given the number of days that have elapsed since January 1, 2000 A.D, your mission is to find the date and the day of the week.

Input

The input consists of lines each containing a positive integer, which is the number of days that have elapsed since January 1, 2000 A.D. The last line contains an integer −1, which should not be processed.
You may assume that the resulting date won’t be after the year 9999.

Output

For each test case, output one line containing the date and the day of the week in the format of "YYYY-MM-DD DayOfWeek", where "DayOfWeek" must be one of "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" and "Saturday".

Sample Input

1730
1740
1750
1751
-1

Sample Output

2004-09-26 Sunday
2004-10-06 Wednesday
2004-10-16 Saturday
2004-10-17 Sunday

这道题做的太坑爹了，竟然每一种情况都得考虑进来，所以出错率特别高，因此这样的方法是不好的，而应该建立一种比较好的范式

#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;
int  wee=0,n,year=2000,month=1,day=1,x;
char week[][10]={"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday","Friday","Saturday"};
bool isleap()
{
  if((year%4==0&&year%100!=0)||year%400==0)
   return 1;
  return 0;
}
void whichday()
{
 while(n>=31)
 {
  //cout<<;
    if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
       n=n-31;
    else
        if(month==4||month==6||month==9||month==11)
            n=n-30;
        else
            if(month==2&&x)
              n=n-29;
            else
                n=n-28;
          month++;

 }
 //cout<<month<<' '<<x<<' '<<n<<' ';
    if(n==30)
        if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
          day=31;
        else
          {
              if(month==2&&x)
                day=2;
              else
                if(month==2&&!x)
                day=3;
              else
                day=1;
           month++;
          }
    else
        if(month==2&&(n==29||n==28))
            if((n==29&&x)||(n==28&&!x))
              {
              day=1;
              month++;
              }
            else
              if(!x&&n==29)
              {
                  month++;
                 day=2;
                 //cout<<day<<"MMMMMMMMMMMM";
              }
              else
                day=n+1;
        else
            day=n+1;
        //cout<<n<<endl;
}
int main ()
{
 cin>>n;
 while(n!=-1)
 {
  year=2000,month=1,day=1;
  int  wee=(n%7+6)%7;
  x=isleap();
  while(1)
  {
   x=isleap();
   if(n>=365)
   {
    if(x)
     if(n>=366)
     {
      n=n-366;
      year++;
     }
     else
      break;
    else
     if(n>=365)
     {
      n=n-365;
      year++;
     }
   }
   else
    break;
  }
        whichday();
  cout<<year<<'-';
  if(month<10)
   cout<<0;
  cout<<month<<'-';
  if(day<10)
   cout<<0;
  cout<<day<<' '<<week[wee]<<endl;
  cin>>n;
 }
 return 0;
}

简便，在找的同时查询时哪一天，思路简单！！！！！！

#include <iostream>
#include <string>       //string类型
#include<cmath>
#include <iomanip>
#include <cstring>    //memset
#include<algorithm>    //sort memset
using namespace std;
char week[][10]={"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday","Friday","Saturday"};
int Year(int year)
{
  if((year%4==0&&year%100!=0)||year%400==0)
   return 366;
  return 365;
}
int Month(int month ,int year)
{
if(month==2)
return Year(year)==366?29:28;
  if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
   return 31;
  else
   return 30;
}
int main()
{
 int n;
 int year,month,day,wee;
 cin>>n;
 while(n>=0)
 {
  year=2000,month=1,day=1;
  wee=(n%7+6)%7;
        while(n)
  {
   if(n>=Year(year))
   {
    n=n-Year(year);
    year++;
   }
   else
    if(n>=Month(month,year))
    {
     n=n-Month(month,year);
     month++;
    }
    else
    {
     day=day+n;
     n=0;
    }
  }
       cout<<year<<'-'<<(month<10?"0":"")<<month<<'-'<<(day<10?"0":"")<<day<<' '<<week[wee]<<endl;//这样的输出格式必须是双引号！！！！！！
  cin>>n;
  
 }
 return 0;
}