Convert Reverse Polish Notation to Infix Expression (Minimal Parentheses)

Problem: Convert Reverse Polish Notation to Infix (Minimal Parentheses) You are given a comma-separated Reverse Polish Notation (RPN) string s. Each token is either: an integer (may have multiple digits), e.g. 2, 13 a binary operator: +, -, *, / Convert the RPN expression into an equivalent infix expression string: The output must be a valid infix expression using + - * /. Use as few parentheses as possible: add parentheses only when needed to preserve operator precedence and associativity and avoid ambiguity. Examples Example 1 Input: 2,1,+,3,* Output: (2+1)*3 Example 2 Input: 4,13,5,+,/ Output: 4/(13+5) Requirements Handle any valid RPN expression. Parentheses in the output should be minimal while preserving the exact meaning. Constraints (assumptions for implementation) 1 <= number of tokens <= 1e5 The expression is guaranteed to be valid. Each integer token length <= 10 Output Return a string representing the infix expression. Example Input 2,1,+,3,* Output (2+1)*3