sizeof C++

Question

int numbers[100];
cout << sizeof(numbers) / sizeof(numbers[0]);

// Outputs 100

Why is it 'sizeof(numbers[0])' and not 'sizeof(numbers[1])' ?

Answer 1

numbers[0] and numbers[1] are both 1 slot in the integer array. Both are of the same size, so it doesn't matter what you choose.

Answer 2

Msizi,
Size of integer variable is 4 byte by default.
And because of that
sizeof(numbers) i. e. the Whole Array Give 400 as there are 100 integers in array each taking 4 bytes of memory 100*4 = 400.

Now sizeof(numbers[0]) is only 4 bytes because it is only One element of the Array.

So, 400/4 gives you 100 in Output.

So output is came out as 100.