A stack-based algorithm transforms mathematical expressions from reverse Polish notation (postfix) to standard infix notation. For instance, the postfix expression “2 3 +” becomes “2 + 3” in infix. This conversion involves reading the postfix expression from left to right, pushing operands onto a stack, and upon encountering an operator, popping the necessary operands, combining them with the operator, and pushing the resulting expression back onto the stack.
This conversion is fundamental in computer science, bridging the gap between a notation convenient for machine evaluation and one readily understood by humans. Its importance stems from the efficiency of postfix evaluation in computers, avoiding the complexities of operator precedence and parentheses inherent in infix notation. Historically, reverse Polish notation has been integral to calculators and certain programming languages.