题解 | #日期差值#

#include <cstdio>
using namespace std;

bool IsLeapYear(int year)
{
    return (year%4==0&&year%100!=0)||(year%400==0);
}

int daytab[2][13]={
    {0,31,28,31,30,31,30,31,31,30,31,30,31},
    {0,31,29,31,30,31,30,31,31,30,31,30,31}
};

int calDays(int min_year,int year,int month,int day)
{
    int all_days=0;
    for(int i=min_year;i<year;i++)
    {
        if(IsLeapYear(i)){
            all_days+=366;
        }
        else all_days+=365;
    }
    

    if(IsLeapYear(year)){
       for(int j=1;j<month;j++)
       {
            all_days+=daytab[1][j];
        }
    }
    else{
        for(int j=1;j<month;j++)
        {
            all_days+=daytab[0][j];
        }
    }    
    all_days+=day;
    return all_days;
}

int main()
{

    int year1,month1,day1,year2,month2,day2;
    scanf("%4d%2d%2d",&year1,&month1,&day1);
    scanf("%4d%2d%2d",&year2,&month2,&day2);
    int min_year=min(year1,year2);
    
    int all_day1=calDays(min_year,year1,month1,day1);
    int all_day2=calDays(min_year,year2,month2,day2);       
    
    cout<<abs(all_day1-all_day2)+1;
    return 0;
}