Question

What is the right way to create a pointer to pointer object? Like for example,

int **foo;
foo = new int[4][4];

Then the compiler gives me an error saying “cannot convert from int (*)[4] to int **.

Thanks.

Answer 1

int **foo = new int*[4];
for (int i = 0; i < 4; i++)
   foo[i] = new int[4];

Clarification:

In many languages the code above is called a jagged array and it’s only useful when the “rows” have different sizes. C++ has no direct language support for dynamically allocated rectangular arrays, but it’s easy to write it yourself:

int *foo = new int[width * height];
foo[y * height + x] = value;