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How can you dynamically allocate a two-dimensional array?

You can dynamically allocate a two-dimensional array by using pointers and the 'new' operator in C++.

In C++, dynamic memory allocation is performed using operators like 'new' and 'delete'. When it comes to two-dimensional arrays, the process is a bit more complex but follows the same principles. A two-dimensional array is essentially an array of arrays, so you need to allocate memory for each of these arrays separately.

Firstly, you need to declare a pointer to a pointer, which will be used to point to the first element of the array. This is done using the syntax 'type **pointerName'. For example, if you're creating an array of integers, you would write 'int **array'.

Next, you allocate memory for the rows of the array. This is done using the 'new' operator, followed by the type of the elements, and the number of elements in square brackets. For example, 'array = new int*[rowCount]'. This creates an array of pointers, each of which will point to a different row of the two-dimensional array.

Then, you need to allocate memory for each row separately. This is done in a loop, where for each iteration, you use the 'new' operator again to allocate memory for the columns of the current row. The syntax is 'array[i] = new int[columnCount]'. This creates an array of integers for each row.

Remember that when you're done with the array, you should deallocate the memory to prevent memory leaks. This is done in reverse order: first, you deallocate each row using 'delete [] array[i]', and then you deallocate the array of pointers using 'delete [] array'.

In summary, dynamic allocation of a two-dimensional array involves creating a pointer to a pointer, allocating memory for the rows, and then for each row, allocating memory for its columns. It's a bit more complex than for a one-dimensional array, but it follows the same principles of dynamic memory allocation in C++.

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