Re-organize "Array, strings và slices" section

[cuonglm]

Describe the bug

The "Array, strings và slices" section has some wrong concepts/definitions, and also somewhat not clearly, since when it introduces strings before slices. The official Go blog has an introduction post about "Arrays, slices (and strings)".

To Reproduce

At revision e19da2e:

1. Wrong definition of uintptr

type StringHeader struct {
    // con trỏ địa chỉ vùng nhớ string
    Data uintptr
    // chiều dài của string
    Len  int
}

This is wrong, Data is an uintptr (Numeric types), not a pointer type, even though its value is the pointer address in memory. This is important concept, otherwise, it can lead to wrong assumption and cause memory corruption. The official Go documentation has a warning for this.

The same problem applies to the slices section:

Data: là con trỏ chứa địa chỉ của một array.

2. Wrong description about len builtin

Tương tự như array, String cũng có một hàm built-in là len dùng để trả về chiều dài của string

len is not a function of String, it's a builtin function, which can take various types of argument, including string type.

3. Wrong word about ranging over slice

Duyệt qua slice thì tương tự như duyệt qua một arrays.

This is not true. Ranging over an array requires copying the array elements, while ranging over slice is not (the same as ranging over pointer to array).

4. The description of slice growing capacity is not quite right

Trong trường hợp slice ban đầu không đủ sức chứa khi thêm vào phần tử, hàm append sẽ hiện thực cấp phát lại vùng nhớ có kích thước gấp đôi vùng nhớ cũ và sao chép dữ liệu sang.

This is only right for slice with < 1024 element, for slice with >= 1024 element, the grow factor is only 1.25 (and the factor can be smoother in go1.18, see https://go-review.googlesource.com/c/go/+/347917)

Expected behavior

Re-organizing the section to follow official Go blog, and also correct all the wrong definition.

[phamtai97]

hi @cuonglm,
Thanks for your feedback. I have reviewed and corrected the issues you mentioned. I created a PR here to fix it.
In the future, we very happy if you can contribute to this project to make this project better for the community.