int day[2] is an array, and there is no predefined way to read in a array.
I think you got your struct date wrong, it should be:
Code:
struct date
{
int month;
int day;
int year;
char dummy;
};
int month[2] will declare two month variables (an array), and I doubt that is what you want .

I also noticed a << in your cin statement, perhaps it should be >> ?