The make function takes the type, length and capacity. If you don’t supply capacity, it defaults to length. So if you want to use append, do something like: make([]int, 0, length)

That will allocate a slice that can fit length ints but has a length of 0 (so append starts at index 0).

You can call len(slice) and cap(slice) to see the difference, but append will insert an element at index len(slice), growing the capacity if necessary