A Common-Sense Guide to Data Structures and Algorithms in Python, Volume 1

Stacks in Action

Although a stack isn’t typically used to store data on a long-term basis, it can be a great tool to handle temporary data as part of various algorithms. Let’s look at an example.

Let’s create the beginnings of a JavaScript linter—that is, a program that inspects a programmer’s JavaScript code and ensures that each line is syntactically correct. JavaScript is notorious for having an abundance of parentheses in its code, so that’s the aspect of syntax we’ll be focusing on. This includes parentheses, square brackets, and curly braces—all common causes of frustrating syntax errors.

To solve this problem, let’s first analyze what type of syntax is incorrect when it comes to braces. If we break it down, we’ll find three situations ...