#include <iostream>
using namespace std;
 
void add_num_of_days(int* month, int* day, int* year, int num_of_days) 
{
struct tm expire_time = {};
int date_to_days;
expire_time.tm_year = *year - 1900;
expire_time.tm_mon = *month - 1;
expire_time.tm_mday = *day;
 
expire_time.tm_mday += num_of_days;
 
mktime(&expire_time);
 
*day = expire_time.tm_mday;
*month = expire_time.tm_mon + 1;
*year = expire_time.tm_year + 1900;
}
 
int main() {
	int month = 1;
	int day = 10;
	int year = 2016;
	add_num_of_days(&month, &day, & year, 100);
	cout << "Month: " << month << ", day:" << day << endl;
}

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