size of a dynamically created array

[hooshdar3]

Hello.
I have declared an array like:

/***********Creating an m*p array**********************/
	 B  = new int *[m];
	 
	 for(row=0;row<m;++row)
       B[row] = new int[p];

How to find the number of elements in it?


The statement
cout << "number of elements in array B equals " << sizeof(B) << endl;
returns 4 each time the program runs

[Hippogriff]

As far as I know when creating elements dynamically like that there is no way to find out the number of elements (as it's just a pointer) so sizeof wont work. Either keep track of the number yourself (in this case 'm') or use vectors.

[condor]

Obviously, B being a m_lines x p_columns (2D) array, the number of its elements is simply the product...m*p. Each of m lines has p elements...That's all!

[upX86]

function sizeof() will always return the size of data type, not the size of block pointed by pointer.