Module leetcode_for_rust::cd0224_basic_calculator

Basic Calculator leetcode: basic_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 .

Example1:

Input: "1 + 1"
Output: 2

Example2:

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

Example3:

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

Note

• You may assume that the given expression is always valid.

• Do not use the eval built-in library function.

Functions

calculate

Solutions