#Stack

Given a string containing `()`, `{}`, and `[]`, determine whether the brackets are properly balanced and valid.

Solve a modified version of the standard Valid Parentheses problem.

Determine if the custom expression containing `{`, `}`, and `*` is balanced. The `*` can act as `{`, `}`, or represent empty.

Validate a custom expression containing '{', '}', and '*' where '*' can act as '{', '}', or empty. Check if it is balanced.

Solve a medium level problem related to stack for matching parentheses. Provide an algorithm and analyze the time complexity.