There are three problem variants of finding the maximum value in a Python dictionary: Find the maximum value and return this maximum value Find the maximum value and return a (key, value) tuple of both the key and the max value itself Find the maximum value and return only the key assigned to the max …
Challenge: This article shows how to sort a Python list using the key argument that takes a function object as an argument. Quick Solution: You can use the lambda function to create the function on the fly as shown in the following example: Explanation: The code uses the key argument and passes a lambda function …
How to Sort in Python with the Lambda Function as Key Argument? Read More »
Knowing the basics is what sets apart the great from the intermediate coders. In other words, a simple and effective way to grow your skills is to learn the basics of computer science. Python Pathfinder Algorithm In this tutorial, you’ll learn about the pathfinder algorithm that recursively determines whether there’s a direct or indirect path …
Challenge: Run a piece of Python code forever—until it is forcefully interrupted by the user. Solution: use a while loop with a Boolean expression that always evaluates to True. Examples: have a look at the following variants of an infinite while loop. You can also use a while condition that always evaluates to True. For …
For a coder, understanding the Quicksort algorithm is like knowing the secret of 42—either you get it, or you don’t belong to the club. If you don’t know either, let’s work on the first one! The Quicksort Algorithm — A Python Implementation The algorithm is a variant of the popular Quicksort algorithm. The function qsort …
Challenge: How to create a multi-line string in Python? In this tutorial, I’ll show you four methods to create and maintain multi-line strings in Python. The most Pythonic ones are the first two methods with triple single quotes ”’ … ”’ or triple double quotes “”” … “”” that wrap a string across multiple lines. …
This tutorial introduces an advanced language feature: lambda functions. Lambda functions are rooted in the mathematical area of lambda calculus. One of the pioneers of this area was Alonzo Church. He introduced lambda functions in 1936 even before the appearance of the first computers. Lambda functions exist in a wide range of languages for functional …
Modifying a sequence while iterating over it can cause undesired behavior due to the way the iterator is build. To avoid this problem, a simple solution is to iterate over a copy of the list. For example, you’ll obtain a copy of list_1 by using the slice notation with default values list_1[:]. Because you iterate …
Python — How to Modify a Sequence While Iterating over It? Read More »
Challenge: How to find a given value in a sorted list? Example: Say, you have a sorted list: Your goal is to find the index of the element 103 in the list. Do you have to check all elements to do this? Well, only if you used the … Naive List Search Algorithm A naive …
Problem: Write a function that joins an arbitrary number of string arguments with a given separator. Example: Given the string arguments “A”, “B”, and “C” and the string separator “-“. Join them to the concatenated string “A-B-C”. Solution: The following code creates a Python function concat() that takes an arbitrary number of arguments, packs them …
The bubble sort does exactly what you’d expect it to do. It sorts an input list by treating each element as a bubble that climbs up the list. Each bubble rises as long as it is greater than the list elements. If a list element is smaller or equal to a list element, the bubble …
This article presents an algorithmic problem with practical value for stock market analysis. For instance, suppose you are trading the cryptocurrency Ethereum. How much profit in dollars can you make by buying low and selling high based on historical data? Maximum Profit Basic Algorithm The max profit algorithm calculates the maximum profit you’d obtain by …
