"""
224. Basic Calculator
Difficulty: Hard
https://leetcode.com/problems/basic-calculator/

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Given a string s representing a valid expression, implement a basic
calculator to evaluate it, and return the result of the evaluation.

Note: You are not allowed to use any built-in function which
evaluates strings as mathematical expressions, such as eval().

 

Example 1:

Input: s = "1 + 1"
Output: 2

Example 2:

Input: s = " 2-1 + 2 "
Output: 3

Example 3:

Input: s = "(1+(4+5+2)-3)+(6+8)"
Output: 23

 

Constraints:

	• 1 <= s.length <= 3 * 10^5

	• s consists of digits, '+', '-', '(', ')', and ' '.

	• s represents a valid expression.

• '+' is not used as a unary operation (i.e., "+1" and "+(2 + 3)" is
invalid).

• '-' could be used as a unary operation (i.e., "-1" and "-(2 + 3)"
is valid).

	• There will be no two consecutive operators in the input.

• Every number and running calculation will fit in a signed 32-bit
integer.
"""

class Solution:
    def calculate(self, s: str) -> int: