题解 | #日期累加#

#include<iostream>
using namespace std;


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


int main(){
    int year = 0;
    int month = 0;
    int day = 0;
    int add = 0;
    
    int months[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 years[2] = {365,366};
    int m = 0;
    cin>>m;
    while(m--){
                // 先进行年判断!
        while(cin>>year>>month>>day>>add){
           // 把前面的天数算上凑个整 
           int days = 0;
           for(int i = 0; i < month; i++){
               days += months[isLeap(year)][i];
           }
            days += day;
            
            add += days; // 相当于在这一年的开头添加的数!
            
            // 先对年处理!
            while(add > years[isLeap(year)]){
                add -= years[isLeap(year)];
                year++;
            }
            // 再对月处理!
            month = 0;
            while(add > months[isLeap(year)][month]){
                add -= months[isLeap(year)][month++];
            }
            day = add;
            
            cout<<year;
            cout<<"-";
            if(month > 9 ){
                cout<<month;
            }else {
                cout<<0<<month;
            }
            cout<<"-";
            if(day > 9){
                cout<<day;
            }else {
                cout<<0<<day;
            }
            cout<<endl;
        }
    }
    return 0;
}