Thread: Dynamic Arrays

One of the easiest ways to do this is to use the vector class to act as a container for your CD class. This is cprogramming's vector tutorial. Let me know if you have any further questions.

An array size has to be a constant value. If you want a dynamic array then you need to use a container class such as std::vector, or simulate an array with new and delete. Both of these have been covered extensively on this forum, if you're willing to search.

Alright, I whipped something up for ya. I use the vector container to store a struct and then display it to the user. Hopefully this will point you in the direction you want to go:

Code:

#include <iostream>
#include <vector>
#include <string>

struct cd {
	std::string Album;
	int numTracks;
};

int main() {

	std::vector<cd> my_DB;
	std::vector<cd>::iterator iDB;
	cd my_CD;

	//now I am using a for loop simply to populate my vector
	//you would most likely load your DB from a file and have 
	//a more complex user input system
	for(int i = 0; i < 2; i++) {
		std::cout<< "Enter the Album name: ";
		std::getline(std::cin, my_CD.Album);
		std::cout << "Enter the number of tracks: ";
		std::cin >> my_CD.numTracks;
		std::cin.get();
		my_DB.push_back(my_CD); //add the structure to the vector container
	}

	//display the information from vector container
	for(iDB = my_DB.begin(); iDB != my_DB.end(); iDB++) {
		std::cout << "The Album name is: " << (*iDB).Album << std::endl;
		std::cout << "The number of tracks is : " << (*iDB).numTracks << std::endl;
	}

	std::cin.get();
	return 0;
}

Originally Posted by Kleid-0

Hey andyhunter, to create kind of a middle minute discussion, why do you always go:
[...]
Why not just add these at the top:
[...]
And call vector, cout, etc, without having to go std:: all of the time?

There is a microscopic chance that he'll include a badly written header to his program in the future, in which 'vector' and/or 'cout' are defined in the global namespace as something else.

To specify std:: is not, by any means, required.