Code Katha

In this blog, we will discuss the "Product of Array Except Self" problem, which is a popular problem in coding interviews. We will go through the problem statement, explain the approach, and provide both brute force and optimal solutions. Additionally, we will perform a dry run of the code for better understanding and analyze the time and space complexity of each solution. Contents [ hide ] Problem Statement with Example Given an integer array nums , the task is to return an array answer such that answer[i] is equal to the product of all the elements of nums except nums[i] . The product of any prefix or suffix of nums is guaranteed to fit in a 32-bit integer. You must write an algorithm that runs in O(n) time and without using the division operation. Let's consider an example to understand the problem: Example 1: Input: nums = [1, 2, 3, 4] Output: [24, 12, 8, 6] Explanation: The product of all elements except the element at index 0 is 2*3*4 = 24 ....

In this blog, we will discuss the "Contains Duplicate" problem, which is a popular problem in coding interviews. We will go through the problem statement, explain the approach, and provide both brute force and optimal solutions. Additionally, we will perform a dry run of the code for better understanding and analyze the time and space complexity of each solution. Contents [ hide ] Problem Statement Given an integer array nums , return true if any value appears at least twice in the array, and return false if every element is distinct. Examples Example 1: Input: nums = [1,2,3,1] Output: true Example 2: Input: nums = [1,2,3,4] Output: false Example 3: Input: nums = [1,1,1,3,3,4,3,2,4,2] Output: true Constraints 1 <= nums.length <= 10 5 -10 9 <= nums[i] <= 10 9 Practice: Leetcode Link Brute Force Solution Algorithm The simplest way to solve this problem is by comparing each element with every other element in the array. If any two ...

In this blog, we will discuss the "Best Time to Buy and Sell Stock" problem, which is a popular problem in coding interviews. We will go through the problem statement, explain the approach, and provide both brute force and optimal solutions. Additionally, we will perform a dry run of the code for better understanding and analyze the time and space complexity of each solution. Contents [ hide ] Problem Statement You are given an array `prices` where `prices[i]` is the price of a given stock on the i-th day. You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock. Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0. Example 1: Input: prices = [7,1,5,3,6,4] Output: 5 Explanation: Buy on day 2 (price = 1) and sell on day 5 (price = 6), profit = 6 - 1 = 5. Note that buying on day 2 and selling on day 1 is not allowed because you m...

The Array Two Sum Problem is a classic problem in computer science and programming. It is often asked in coding interviews and serves as a good exercise for beginners to learn about arrays, loops, and hash maps. In this blog, we will explore the problem statement, understand different approaches to solve it, and analyze the time and space complexity of each solution. Contents [ hide ] Problem Statement Given an array of integers `nums` and an integer `target`, return indices of the two numbers such that they add up to the target. You may assume that each input would have exactly one solution , and you may not use the same element twice . Example 1: Input: nums = [2, 7, 11, 15], target = 9 Output: [0, 1] Explanation: Because nums[0] + nums[1] == 9, we return [0, 1]. Example 2: Input: nums = [5, 3, 1, 7, 8], target = 10 Output: [1, 3] Explanation: Because nums[1] + nums[3] == 10, we return [1, 3]. Practice: Leetcode Link Brute Force Solution The brute force ...