Solution: Basic Calculator
Explore how to implement a basic calculator that evaluates expressions containing integers, plus and minus operators, and parentheses. Understand the stack pattern to handle nested subexpressions by pushing and popping intermediate results. This lesson guides you through building the solution step-by-step and explains its time and space complexity for efficient coding interview preparation.
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