Write a programm in c++ which accepts a date,month and year and show the date ,month and year before 50 days by using structure [on hold]

struct date
{
    int day;
    int month;
    int year;
};

int main (){
    return 0;
}

Can someone please explain how to write the logic for above question. I am new in C++, not able to understand how to use structure and its logic.