Solve tree view and parentheses cleanup

Solve the following two algorithm problems. 1. Right-side view of a binary tree Given the root of a binary tree, return the values of the nodes that would be visible if you looked at the tree from its right side, listed from top to bottom. Example: - Input: root = [1,2,3,null,5,null,4] - Output: [1,3,4] 2. Remove the minimum invalid parentheses Given a string `s` containing lowercase English letters and the characters `(` and `)`, remove the minimum number of parentheses so that the resulting string is valid. A string is valid if: - every opening parenthesis has a matching closing parenthesis, - parentheses are properly ordered, - letters may appear anywhere and do not affect validity. Return any valid string after the minimum removals. Examples: - Input: `a)b(c)d` Output: `ab(c)d` - Input: `))( (` Output: `` - Input: `(a(b(c)d)` Output: `a(b(c)d)`