Max Array?

[Shakespeare]

I am reading data from a file and i need to read in a lot of data, approaching millions of lines proabably.

the problem i have is i have declared a struct to store the data but i have found that the maximum array of structs i can have is:

users db[28725] ;

Anyone know why this is and how i can change it to accept a larger amount of data. my struct is simple:

struct users
{
	string user ;
	char ip[20] ;
} ;

Thanks Guys