- https://www.geeksforgeeks.org/fundamentals-of-algorithms/#SearchingandSorting 5 parts
- https://www.geeksforgeeks.org/analysis-of-algorithms-set-1-asymptotic-analysis/
- https://towardsdatascience.com/understanding-time-complexity-with-python-examples-2bda6e8158a7
- https://stackoverflow.com/questions/55087761/how-to-calculate-time-complexity-on-of-the-algorithm
- https://stackoverflow.com/questions/11032015/how-to-find-time-complexity-of-an-algorithm
- https://www.google.com/search?q=depth+first+search&oq=depth+fir&aqs=chrome.0.0j69i57j0l4.2847j0j7&sourceid=chrome&ie=UTF-8
- https://www.google.com/search?q=breadth+first+search&oq=brea&aqs=chrome.2.69i57j0l2j69i60l2j0.3128j0j7&sourceid=chrome&ie=UTF-8
- https://www.google.com/search?q=matching+parenthesis&oq=matching+parenthesis+&aqs=chrome..69i57j0l5.4799j0j7&sourceid=chrome&ie=UTF-8
- https://www.tutorialspoint.com/python/python_hash_table.htm