README_EN.md

comments	difficulty	edit_url	tags
true	Hard	https://github.com/doocs/leetcode/edit/main/solution/0700-0799/0772.Basic%20Calculator%20III/README_EN.md	Stack Recursion Math String

772. Basic Calculator III 🔒

中文文档

Description

Implement a basic calculator to evaluate a simple expression string.

The expression string contains only non-negative integers, '+', '-', '*', '/' operators, and open '(' and closing parentheses ')'. The integer division should truncate toward zero.

You may assume that the given expression is always valid. All intermediate results will be in the range of [-231, 231 - 1].

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 = "6-4/2"
Output: 4

Example 3:

Input: s = "2*(5+5*2)/3+(6/2+8)"
Output: 21

 

Constraints:

• 1 <= s <= 104
• s consists of digits, '+', '-', '*', '/', '(', and ')'.
• s is a valid expression.

Solutions

Solution 1

Python3

Java

C++

Go