Pointers & Multidimensional Arrays

I were troubled by the use of pointers to access array in C. I worked on it and created a method to deal with it.

• array_name is a constant pointer.

It points the first location of the array.

array_name =  &array_name[0]
 *array_name = array_name[0]

Pointers are incremented by its sizeof(type).

array + i = &array_name[0]
 *array + i = array_name[i]

• 2D Array is an array of constant pointers.

So to access an element

array_name[i][j]

First you have to access constant pointer stored in the i-th location of the array pointed by pointer array_name. So increment array_name by i.

*(array_name+i)

Then you have to access the j-th location of the array pointed by the above pointer.

*(array_name+i)+j

To get the value of that location use the derefence operator.

*(*(array_name+i)+j)

• 3D Array is a 2D array of constant pointers

So to access an element

array_name[i][j][k]

First you have to access the pointer stored in the i-th location of the array pointed by the pointer array_name.

*(array_name)+i

Then you have to access the j-th element in that array

*(*(array_name)+i)+j

Which itself is a pointer. Increment it k times to get the k-th location.

(*(*(array_name)+i)+j)+k

Then derefernce it to get the value of that location.

*(*(*(array_name)+i)+j)+k)

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