Stack Applications
Detailed guide and Python implementation for the 'Stack Applications' problem.
Problem Statement
Write a function evaluate_postfix(expression) that takes a string of space-separated tokens expression representing a postfix expression and evaluates it, returning the resulting integer.
- •1 <= len(expression) <= 100
- •Operators are +, -, *, /
Examples
expression = "2 3 1 * + 9 -"
-4
The evaluation order is: 3 * 1 = 3; 2 + 3 = 5; 5 - 9 = -4.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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