💡 Problem Formulation: We aim to find and sum all the truncatable primes that are less than a given number, n. A truncatable prime is a prime number that remains prime when digits are truncated one at a time from either the left or right side. For instance, if n is 100, then the truncatable … Read more
💡 Problem Formulation: The challenge is to write a Python function that finds the smallest substring in a given string, which contains all the characters of another string. For example, given the string “ADOBECODEBANC” and the pattern “ABC”, the smallest window that contains all the characters (A, B, and C) is “BANC”. Method 1: Naive … Read more
💡 Problem Formulation: Imagine you are given an array of distinct positive integers. Your task is to identify the smallest positive integer that cannot be generated by summing any subset of the array’s elements. For example, if the input array is [1, 2, 3], the smallest positive integer that cannot be represented as a sum … Read more
💡 Problem Formulation: This article demonstrates how to calculate the probability of being in a specific state at a given time in a Markov chain using Python. Given a Markov transition matrix and an initial state distribution, we seek the probability distribution at a later time step. The input is a state transition matrix and … Read more
💡 Problem Formulation: Imagine a scenario where we have multiple boxes, and a ball is placed in one of them. The challenge is to determine the index position of the box containing the ball using Python. For example, given a list of boxes [“box1”, “box2”, “ball”, “box3”], we aim to find the position of the … Read more
💡 Problem Formulation: This article explores solutions for determining which player can first rearrange the characters of a given string to form a palindrome. A player wins if they can form a palindrome by swapping characters in the string. The input is a string, such as “mamad” and the expected output is the player number … Read more
💡 Problem Formulation: Given a matrix where only the largest elements in each row and column are known, the challenge is to reconstruct the original matrix. Assume you are given two arrays: one representing the largest values in each row, and the other for columns. For example, if the row array is [3, 5, 4] … Read more
💡 Problem Formulation: The task at hand is to identify the longest continuous substring within a given string, which consists of either all letters or all digits. For instance, in the input “a123b4cde57fghij789k0”, the desired output for digits would be ‘789’, and for letters, it would be ‘fghij’, as these are the longest uninterrupted sequences … Read more
💡 Problem Formulation: You want to find all keys in a dictionary that share the same value. For instance, given a dictionary {‘a’: 1, ‘b’: 1, ‘c’: 2, ‘d’: 3}, the goal is to identify ‘a’ and ‘b’ as duplicates because they both have the value 1. Method 1: Using a Default Dictionary To find … Read more
5 Best Ways to Find k Longest Words in a Given List in Python 💡 Problem Formulation: We often encounter scenarios in programming where we need to filter data based on certain criteria. Specifically, finding the k longest words from a list is a common task that can be implemented in various efficient ways using … Read more
💡 Problem Formulation: When working with lists in Python, you may encounter elements with None values. Identifying the positions of these None values is often a necessity, for instance, in data cleaning tasks where missing values need to be dealt with. Suppose you have a list [1, None, 2, None, 3], and you want to … Read more
💡 Problem Formulation: You have a Python list of integers and you want to identify all subsequences where the numbers are in a strictly increasing order. For instance, given the input list [1, 2, 5, 3, 4], the desired output would be [[1, 2, 5], [3, 4]] since these are the groups within the list … Read more