题解 | #日期累加#

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

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 isleapyear(int y){
    return (y%4==0&&y%100!=0 )||(y%400==0);
}
int main() {
    int n;
    cin>>n;
    while (n-->0) {
    int year,month,day,dd;
    cin>>year>>month>>day>>dd;
    int row=isleapyear(year);
    dd+=day; //全变成每月的1号

    while (dd>dayTab[row][month]) {
        dd-=dayTab[row][month];
        month++;
        if(month>12){
            month=1;
            year++;
            row=isleapyear(year);
        }

    }
    printf("%04d-%02d-%02d\n",year,month,dd);
    }
}
// 64 位输出请用 printf("%lld")