2867.回文日期

此题可视作466.回文日期的拓展

#include<bits/stdc++.h>
using namespace std;

int months[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

bool check(int date)
{
    int year = date / 10000;
    int month = date % 10000 / 100;
    int day = date % 100;

    if (!month || month >= 13 || !day) return false;

    if (month != 2 && day > months[month]) return false;
    if (month == 2)
    {
        bool leap = year % 4 == 0 && year % 100 || year % 400 == 0;
        if (day > 28 + leap) return false;
    }

    return true;
}

int main()
{
    int date;
    bool f=false;
    cin >> date;
    int temp=date/10000;//取前四位
    for (int i = temp; i < 10000; i ++ )
    {
        int x = i, r = i;
        for (int j = 0; j < 4; j ++ ) r = r * 10 + x % 10, x /= 10;
        if (check(r)&& !f && r>date){
            f=true;
            cout<<r<<endl;
        }
        if(i/1000==i%100/10 && i/100%10==i%10 &&i%10!=i/1000 &&check(r)&& r>date){
            cout<<r<<endl;
            break;
        }
    }
    return 0;
}