Arrays
Declaring
The type of the elements and the number of elements are required:
int my_array[100]; // an integer array of size 100
Initializing
Declaring and initializing an array:
int my_array[] = { 1, 2, 3, 4, 5 };
No need to specify the size, it is inferred from the number of the elements.
Accessing elements
Access via the bracket syntax
int my_array[] = { 1, 2, 3, 4, 5 };
printf("The 2nd element is %d", my_array[1]);
Size of arrays
The sizeof operator is used to obtain the total number of bytes in aggregate in an array.
The evaluation is a compile-time eval with no cost during runtime.
int ar[] = { 1, 2, 3, 4, 5 };
size_t n_elements = sizeof(ar) / sizeof(int); // used a lot in older code, a hack
The std::size function from the <iterator> header is a more modern approach