Amazon Frontend Engineer System Design Questions

In order to optimize rendering performance in Amazon's web applications, a Virtual DOM is used for efficient updates. This problem involves designing the diffing algorithm which reconciles changes in a virtual representation of the DOM.
### Class Signature
python
class VirtualDOM {
def create_element(self, tag: str, props: dict, children: List[Union[str, 'VirtualDOM']]) -> None:
# Create a virtual DOM element
def diff(self, old_tree: 'VirtualDOM', new_tree: 'VirtualDOM') -> List[str]:
# Compute the difference between two trees
}
### Example Method Signatures
- create_element(tag: str, props: dict, children: List[Union[str, 'VirtualDOM']]) -> None: Creates a virtual DOM element.
- diff(old_tree: 'VirtualDOM', new_tree: 'VirtualDOM') -> List[str]: Returns a list of operations needed to update the DOM based on differences.### Example 1:
Input:
old_tree = create_element('div', {'id': '1'}, ['Hello', 'World'])
new_tree = create_element('div', {'id': '1'}, ['Hello', 'Amazon'])
Output: ['UPDATE_TEXT: 1, Amazon']
### Constraints:
- 1 <= number of elements in tree <= 1000
- Tags and props are limited to valid HTML attributes.