Calculator with Basic Operations and Parentheses

Calculator Implement a basic calculator to evaluate a simple expression string. The expression string may contain open ( and closing parentheses ), the plus + or minus sign -, non-negative integers, and empty spaces . The expression string contains only non-negative integers, +, -, *, / operators, open and closing parentheses ( and ), and spaces . The integer division should truncate toward zero. Input A string representing a valid arithmetic expression containing non-negative integers, +, -, *, / operators, parentheses, and spaces. Output The integer result of the arithmetic expression. Example Input: 2*(5+5*2)/3+(6/2+8) Output: 21 Input: (2+6*3+5-(3*14/7+2)*5)+3 Output: -12 Constraints The expression only contains integers and operators. The result is guaranteed to fit within a 32-bit signed integer. Example Input 2*(5+5*2)/3+(6/2+8)