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Evaluate Reverse Polish Notation

Implement a program that evaluates the value of an arithmetic expression in Reverse Polish notation (RPN). The expression is represented as an array of strings where each string is either an operand or an operator. Valid operators are '+', '-', '*', and '/'. Return the final result of the expression. Input format: A single line with space-separated tokens representing the RPN expression. Output format: Print a single integer result of the evaluated expression. Example: Input: 2 1 + 3 * Output: 9

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stackrpnevaluation

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