题解 | #打印日期#

#include <cstdio>
#include <iostream>
using namespace std;
int timevault[2][12] = {{31,29,31,30,31,30,31,31,30,31,30,31},{31,28,31,30,31,30,31,31,30,31,30,31}};  //致敬经典万智牌时之库 （Time Vault）
int main() {
    int year, day;
    while (cin >> year >> day) 
    { // 注意 while 处理多个 case
       // cout << a + b << endl;
       if (((year % 4 == 0)&&(year % 100 != 0))||year % 400 == 0) //分闰年处理
     {
       int counter = 0; //月份
       while (day > 0) 
       {
         if (day - timevault[0][counter] > 0) 
         {
            day -= timevault[0][counter] ;
            counter++;
         }else 
         {
            break;   //不够减了，月份已得出，退出循环。
         }
       }
         printf("%4d-%02d-%02d\n",year,counter + 1,day);  //因为数组缘故，counter比实际月份小1
     }else 
     {
            int counter = 0;
            while (day > 0) 
         {
         if (day - timevault[1][counter] > 0) 
          {
             day -= timevault[1][counter] ;
             counter++;
          }else 
          {
             break;
          }
          
         }
             printf("%4d-%02d-%02d\n",year,counter + 1,day);
     }

       
    
    }
}
// 64 位输出请用 printf("%lld")