Wrong solution for stack copy

[Arquestro]

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In the test example of 1.3.12 exercise, the first(or head) element of the stack should be 4, not 1. The copy of the stack is done in reverse, breaking it's structure: https://github.com/ChangeMyUsername/algorithms-sedgewick-python/blob/15007b02081f5e398aeb316f5935ce9c97e59ca8/chapter_1/module_1_3.py#L154

I suppose it should be done through another temporary stack to ensure structure integrity:

    # 1.3.12 practice
    @classmethod
    def copy(cls, old_stack: Stack) -> None:
        """
        Copy existing stack and return new stack.
        Args:
            cls: Stack class
            stack (Stack): existing stack
        Returns:
            Stack: new stack
        >>> s = Stack()
        >>> s.push(1)
        >>> s.push(2)
        >>> s.push(3)
        >>> s_copy = Stack.copy(s)
        >>> s_copy._first.val
        3
        >>> s_copy.size()
        3
        >>> for item in s_copy:
        ...     print(item)
        ...
        3
        2
        1
        """
        s_tmp = cls()
        s_copy = cls()
        if isinstance(old_stack, Stack) and not old_stack.is_empty():
            for item in old_stack:
                s_tmp.push(item)
            for item in s_tmp:
                s_copy.push(item)
        return s_copy

O(N) time is expected. But O(N) space, I don't think we can avoid that.

And I guess the constructor here should be changed too, because it has the same behaviour: https://github.com/ChangeMyUsername/algorithms-sedgewick-python/blob/15007b02081f5e398aeb316f5935ce9c97e59ca8/chapter_1/module_1_3.py#L37

Maybe even make the option to make a copy in 'init' if there is a 'Stack' in 'args'.

[ChangeMyUsername]

Sorry for the late reply (getting lazy these days...), issues you mentioned have been updated, you can check and see if any further issues.

[Arquestro]

It's all right, no stress :) Just want to mention, that constructor behaviour is the same as old copy, it should be changed to self.copy instead of pushing, imo.

[ChangeMyUsername]

These fixes are not optimized, should be a better approve for this solution