Solution: Basic Calculator
Explore how to solve arithmetic expression evaluation using the stack pattern in Python. Understand how to process digits, operators, and nested parentheses by pushing and popping intermediate results, enabling you to build an efficient basic calculator algorithm with O(n) time complexity.
Statement
Given a string containing an arithmetic expression, implement a basic calculator that evaluates the expression string. The expression string can contain integer numeric values and should be able to handle the “+” and “-” operators, as well as “()” parentheses.
Constraints:
Let s be the expression string. We can assume the following constraints:
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s.length