Accessing elements of multi-dimensional arrays of various dimensions

To access an array element using array notation, we must be consistent in using both the dimensions of the array and a valid range of offsets for each dimension.

To access an element of an array, we would use the [ and ] notation for each of its offsets in each dimension. Remember that C indices are zero-based. It is better to think of them as offsets from the array base—for example, the column offset for the first element in a 1D array is [0]; the row offset for the first row of a 2D array is [0][x]; the layer offset for the first layer of a 3D array is [0][y][x]. Putting this knowledge to work, let's access the third element of our various arrays, as follows:

int third;

first = array1D[2];       // third element.

first = array2D[0][2];    // third element of 1st row.

first = array3D[0][0][2]; // third element of 1st layer and 

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