Given a string s representing a valid arithmetic expression with integers and the operators +, -, *, /, evaluate the expression and return its value. The integer division should truncate toward zero.

Example 1:

Input: 3+2*2
Output: 7

Example 2:

Input: 3/2
Output: 1

Example 3:

Input: 3+5/2
Output: 5

Constraints:

• 1 ≤ s.length ≤ 3 × 10⁵
• s consists of integers, +, -, *, /, and spaces
• s represents a valid expression
• All integers are non-negative, result fits in a 32-bit signed integer

Input format: One line — the arithmetic expression string.

Output format: Integer result.