题解 | 打印日期

#include <climits>
#include <iostream>
using namespace std;

int GetMonthDay(int year,int month)
{
    int months[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
    if(month==2 && (year%4==0 && year%100!=0 || year%400==0))
        return 29;
    else return months[month];
}

int main() 
{
    int year,day;
    while(cin >> year >> day)
    {
        int _month=1,_day=day;
        while(_day>GetMonthDay(year,_month))
        {
            _day-=GetMonthDay(year, _month);
            ++_month;

            if(_month>12)
            {
                year++;
                _month=1;
            }
        }
        printf("%04d-%02d-%02d\n",year,_month,_day);
    }
}
    
// 64 位输出请用 printf("%lld")