Evaluate the value of an arithmetic expression in **Reverse Polish Notation** (Postfix Notation).
Valid operators are `+`, `-`, `*`, and `/`. Each operand may be an integer or another expression.
Note that division between two integers should truncate toward zero (e.g., `13 / 5 = 2` and `-13 / 5 = -2`).
It is guaranteed that the given RPN expression is always valid and will not result in division by zero.
### Constraints
- `1 <= tokens.length <= 10^4`
- `tokens[i]` is either an operator (`+`, `-`, `*`, `/`) or an integer in the range `[-200, 200]`.
### Input Format
A single line containing space-separated tokens of the Reverse Polish Notation expression.
### Output Format
Print a single integer representing the evaluated result.
Sample Cases
Example 1Sample Case
Input: 2 1 + 3 *
Output: 9
Example 2Sample Case
Input: 4 13 5 / +
Output: 6
Example 3Sample Case
Input: 2
Output: 2
Example 4Sample Case
Input: 222222
Output: 222222
Constraints
Runtime Limit: 2000 ms per test batch
Memory Limit: 256 MB
Standard I/O stream reading
Official submissions are evaluated against hidden test cases on the server to verify time & memory complexity.