💡 Problem Formulation: Given an unsorted array of integers, the task is to find the smallest positive integer that is missing from the array. For instance, with an input array [3, 4, -1, 1], the desired ouput is 2, since it’s the smallest missing positive integer that doesn’t appear in the list. Method 1: Sorting … Read more
💡 Problem Formulation: This article discusses how to find the k-th last element in a singly linked list using Python. For instance, given a linked list node1 -> node2 -> node3 -> node4 -> node5 and k=2, the desired output would be node4. Method 1: Two-Pass Algorithm The two-pass algorithm involves two iterations: the first … Read more
💡 Problem Formulation: You are provided an unsorted array containing n non-negative integers. The task is to find the smallest missing positive integer that does not occur in the array. For example, given the array [3, 4, -1, 1], the lowest missing positive integer is 2. This article will guide you through five different methods … Read more
💡 Problem Formulation: You are given a list of stacks where each stack contains integer elements. The challenge is to maximize the sum by popping exactly k elements from any stacks. For example, given stacks [[2, 3, 1], [5, 4], [9, 7]] and k = 3, the maximum sum is achieved by popping 9 + … Read more
💡 Problem Formulation: In any organization, it is essential to recognize and reward good performers. Let’s say we have a list of employees with their respective performance scores. Our goal is to determine the minimum total payment to be distributed among all employees who are considered good performers based on a certain score threshold. For … Read more
💡 Problem Formulation: Imagine you have a list of numbers and you need to analyze every ‘window’ or segment of size k to ensure that each number within that window is unique. For example, given the list [1, 2, 3, 4, 2, 5] and a window size k = 4, we want to find which … Read more
💡 Problem Formulation: We are often presented with unique and interesting algorithmic challenges in programming. One such problem is determining whether a given integer can be represented as a sum of distinct factorial numbers. These numbers are the products of an integer and all the integers below it, such as 5! = 5*4*3*2*1. For example, … Read more
💡 Problem Formulation: Given a two-dimensional grid map representing an island, where ‘1’s represent land and ‘0’s represent water, our goal is to find the total perimeter of the island(s). For instance, an input of [[1, 1, 0, 0], [1, 1, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]] should yield an output … Read more
💡 Problem Formulation: Binary trees are a fundamental data structure in computer science. In this article, we tackle the challenge of inverting a binary tree, transforming each node’s left subtree into its right subtree, and vice versa. A given input tree like {a, {b, d, e}, {c, f, g}} should be transformed to output {a, … Read more
💡 Problem Formulation: We are aiming to interleave the elements from two different linked lists in Python. For example, having two linked lists A->B->C and 1->2->3, we want to merge them into a single list A->1->B->2->C->3. This article discusses five different ways to accomplish this task, taking into account efficiency, readability, and versatility of the … Read more
💡 Problem Formulation: Inorder traversal is a fundamental algorithm to process binary trees. It involves visiting the left subtree, the root node, and then the right subtree recursively. In Python, there are several approaches to achieve this. Suppose we have a binary tree; our objective is to visit each node in ascending order per inorder … Read more
💡 Problem Formulation: We aim to count all the positive n-digit integers where each digit is strictly greater than the preceding one. For example, given n = 2, our desired output is 45, since there are 45 two-digit numbers (such as 12, 34, 78) where each pair of digits adheres to this rule. Method 1: … Read more