Evaluate Postfix Arithmetic with Truncating Integer Division
Company: Google
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Other
### Problem
Evaluate a valid arithmetic expression written in reverse Polish notation. Tokens are integer operands or the binary operators `+`, `-`, `*`, and `/`. Division truncates toward zero, and no division by zero occurs. Return the resulting integer.
```cpp
int evalRPN(vector<string>& tokens);
```
### Examples
```text
Input: tokens = ["8","3","-","2","*"]
Output: 10
```
```text
Input: tokens = ["-7","3","/"]
Output: -2
```
### Constraints
- There are between 1 and 10000 tokens.
- Numeric tokens represent integers between -200 and 200.
- The expression is valid, and its answer and every intermediate calculation fit signed 32-bit integers.
Overview: Evaluate postfix arithmetic with ordered stack operands and exact integer division truncating toward zero.