题解 | 日期累加

#include <iostream>
#include <stdio.h>
using namespace std;
void NextDay(int& year, int& month, int& day) {
    //月份对应天数
    int dayOfmonth[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; //7.8月都是31天
    bool isLeap;
    isLeap = year % 400 == 0 || year % 100 != 0 && year % 4 == 0;
    //是否是闰月
    if (isLeap) {
        dayOfmonth[2] = 29;
    }
    ++day;
    if (day > dayOfmonth[month]) {
        day = 1;
        month++;
    }
    if (month > 12) {
        month = 1;
        year++;
    }

}
int main() {
    int m;
    scanf("%d", &m);
    int i, year, month, day, num;
    for (i = 0; i < m; ++i) {
        scanf("%d%d%d%d", &year, &month, &day, &num);
        int next = 0; //加的次数
        while (1) {
            NextDay(year, month, day);
            next++;
            if (next == num) {
                break;
            }
        }
        printf("%04d-%02d-%02d\n", year, month, day);

    }
}
// 64 位输出请用 printf("%lld")