Initialize an array within a struct

[slicktacker]

Hi all,

I'm implementing a list of arrays like so:

struct Cell {
    int arrayValues[5];
    Cell *next;
};
Cell *head;

How do I write the structure such that all arrayValues are set to 0? I'm trying to use a for loop

for(int i = 0; i < 5; i++)
    head->valueArray[i] = 0;

outside of the struct but I'm not sure what I'm doing. Thanks for your help!

[7stud]

That is what constructors are for:

#include <iostream> 
using namespace std;

struct Cell 
{
	Cell()
	{
		for(int i=0; i<5; ++i)
		{
			data[i] = 0;
		}

		next = 0;
		
	}
	
	int data[5];
	Cell* next;
};	


int main ()  
{
	Cell c;   //This statement calls the constructor
	cout<<c.data[4]<<endl;  //0

	cout<<">>>Hit Enter to Quit";
	cin.get();
	return 0;
}

You can accomplish the same thing outside the struct like this:

#include <iostream> 
using namespace std;

struct Cell 
{
	int data[5];
	Cell* next;
};	


int main ()  
{
	Cell c;
		
	for(int i=0; i<5; ++i)
	{
		c.data[i] = 0;
	}
	
	c.next = 0;
	
	cout<<c.data[4]<<endl;  //0
	 
	cout<<">>>Hit Enter to Quit";
	cin.get();
	return 0;
}

[slicktacker]

Ah, thanks a lot! I never knew about constructors in structs. Thanks again!

[treuss]

I never knew about constructors in structs.

C++ structs are exactly the same as C++ classes, with the tiny difference that the default visibility for struct members is public (private for class members).