func alloc(size: u64) -> unit mut*:
	foreign func malloc(size: u64) -> unit mut*
	return malloc(size)

foreign func free(ptr: unit*)

let array = alloc(400ul) as i32 mut*
*array = 10
*(array + 1) = 20
let q = array + 10
let n = q - array
array[5] = 50
free(array as unit*)