题解 | #日期差值#

#include <iostream>
using namespace std;
int confess(int month,int * ripple)
{
    int ret = 0;
    for (int i = 0; i < month; i++)
    {
        ret += ripple[i];
    }
    return ret;
}

int mystic(int a1, int b1, int c1,int ret)
{
    int mangy = a1 * 365 + a1 / 400 + a1 / 4 - a1 / 100;
    if (b1 > 2 && (a1 % 400 == 0) || b1 > 2 && (a1 % 4 == 0 && a1 % 100 != 0))
    {
        mangy += 1;
    }
    mangy += ret;
    mangy += c1;
    return mangy;
}
int main() {
    int a, b;
    int ripple[13] = { 0, 31,28,31,30,31,30,31,31,30,31,30,31 };
    while (cin >> a>>b ) 
    { 
        int a1, a2, b1, b2, c1, c2;
        a1 = a2 = b1 = b2 = c1 = c2 = 0;

        c1 = a % 100;
        a /= 100;
        b1 = a % 100;
        a /= 100;
        a1 = a; 

        c2 = b % 100;
        b /= 100;
        b2 = b % 100;
        b /= 100;
        a2 = b;

        
        int ret1 = confess(b1, ripple);
        int ret2 = confess(b2, ripple);

        int  pause1 = mystic(a1,b1,c1,ret1);
        int  pause2 = mystic(a2,b2,c2,ret2);

        cout << abs(pause1 - pause2) + 1 << endl;//这个+1还挺重要
        //cout << a1 << "  " << b1 << "   " << c1 << "   " << endl << a2 << "    " << b2 << "    " << c2;
        //cout << ret1<<ret2;
    }
}