Division in Python

The double-frontslash // operator performs integer division and the single-frontslash / operator performs float division. An example for integer division is 40//11 = 3. An example for float division is 40/11 = 3.6363636363636362. A crucial lesson you need to master as a programmer is “division in Python”. What does it mean to divide in Python? … Read more

A RegEx to Match Bitcoin Addresses

What regular expressions can be used to match Bitcoin addresses? A regular expression for validating Bitcoin addresses must check that the string is 26-35 characters long, start with “1” or “3” or “bc1” consists of uppercase or lowercase alphabetic and numeric characters, and ensure it doesn’t contain ambiguous characters. Not allowed are the uppercase letter … Read more

Python Multiplication Operator

Python’s multiplication operator * multiplies two objects. The semantics of the multiplication depends on the operands’ data types. For example, multiplying two integers performs arithmetic multiplication whereas multiplying a list with an integer performs list concatenation. The specific return value of the multiplication operator is defined in a data types’ __mul__() magic method. Have a … Read more

Five Types of Inheritance in Python

In a previous article, we introduced the topic of object-oriented programming, or OOP for short. Then, we discussed classes and the topic of inheritance. This article will do a quick recap of inheritance, what it is, and why you’d use it. Then we’ll introduce the different types of inheritance you might encounter in your programming … Read more

[Google Interview] Find All Numbers That Disappeared in an Array

[toc] ?๏ธ Company Tags: Google Problem Formulation Given an array nums of n integers. Return an array containing all the integers in the range[1, n]that do not appear in nums. โœ’๏ธ Here, nums[i] is in the range [1, n]. โš ๏ธConstraints: n == nums.length 1 <= n <= 105 1 <= nums[i] <= n ?Examples Letโ€™s have a look at some … Read more

Python Subtraction Operator

Python provides the subtraction operator – to subtract one object from another. The semantics of the subtraction depends on the operands’ data types. For example, subtracting two integers performs the arithmetic difference operation whereas subtracting two sets performs the set difference operation. The specific return value of the minus operator is defined in a data … Read more

Python Program to Add Two Numbers

Add Two Integers The most basic Python program to add two integer numbers stored in variables num_1 and num_2 is the expression num_1 + num_2 using the addition operator. The following code shows how to add two numbers 20 and 22 and print the result 42 to the shell: Add Two Integers with User Input … Read more

Python Addition Operator

Python provides the addition operator + to add two objects. The semantics of the addition depends on the operands’ data types. For example, adding two integers perform arithmetic addition whereas adding two lists performs list concatenation. The specific return value of the addition operator is defined in a data types’ __add__() magic method. Have a … Read more

How to Generate a Random String in Python?

Problem Formulation You are tasked with writing Python code to generate a random string.  The string should contain any of the printable characters on your keyboard.  Letters, numbers, and punctuation marks are valid, and weโ€™ll leave out any whitespace characters. Whatโ€™s the best way to solve this in Python? Method 1: List Comprehension and random.randint() … Read more

K-Nearest Neighbors (KNN) with sklearn in Python

The popular K-Nearest Neighbors (KNN) algorithm is used for regression and classification in many applications such as recommender systems, image classification, and financial data forecasting. It is the basis of many advanced machine learning techniques (e.g., in information retrieval). There is no doubt that understanding KNN is an important building block of your proficient computer … Read more

Python Not Equal To

The Python not equal to (left!=right) operator returns True when its left operand is not equal to its right operand as defined by the __ne__() magic method. Otherwise, it returns False. For example, 3!=2 evaluates to True, but 3!=3 evaluates to False. Examples Let’s explore a couple of examples regarding the not equal to operator. … Read more