Expression Evaluation & Parsing

Expression Types

• Infix : a + b * c
• Postfix (RPN): a b c * +
• Prefix: + a * b c

Stack - Based Evaluation

• Convert Infix into Postfix using Stack (Shunting Yard Algorithm)
• Evaluate Postfix using stack:
  • If operand - push
  • If operator pop two operands, evaluate, push result

Problems

• Evaluate Reverse Polish Notation (150)
• Infix to Postfix Convertor
• Basic Caculator
• Expression Parsing