The hottest Recursion Substack posts right now

And their main takeaways
Category
Top Technology Topics

The surreal numbers

Infinitely More • 41 implied HN points • 06 Jan 24
🔬 Science Mathematics Numbers Recursion
  1. The surreal numbers unify various number systems into one comprehensive system.
  2. Surreal numbers are generated through a recursive process of completion and ordering.
  3. The surreal number generation rule involves separating existing numbers into lower and upper sets to create new numbers.

Looking at the Datastructures- Trees [Math Mondays]

Technology Made Simple • 179 implied HN points • 18 Jul 23
🕹 Technology Data Structures Software Engineering Machine Learning AI Recursion
  1. Trees are powerful data structures that are great for efficient organization and retrieval of data in software engineering.
  2. Recursion works well with trees due to their recursive substructure, making implementation of recursive functions easier.
  3. Decision trees in AI excel at discerning complex patterns, providing interpretable results, and are versatile in various domains such as finance, healthcare, and marketing.

[Solution]Problem 76: Combination Sum [Google]

Technology Made Simple • 59 implied HN points • 24 Feb 23
🕹 Technology Programming Algorithms Graphs Recursion Backtracking
  1. The problem involves backtracking, recursion, and graph modeling to find unique combinations that sum to a target.
  2. Modeling the problem as a graph with states and transitions helps in traversal mechanics using DFS.
  3. Implementing a simple graph traversal algorithm, backtracking, and a global variable to track combinations can efficiently solve the problem.

[Solution]Problem 70: Pow(x,n) [Amazon]

Technology Made Simple • 59 implied HN points • 23 Dec 22
🕹 Technology Math Logic Optimization Recursion
  1. The post discusses a solution to Problem 70, which involves calculating a number raised to a power using math, logic, optimization, and recursion.
  2. The problem statement requires implementing a function that calculates x raised to the power n, with specific input-output examples provided.
  3. Constraints for the problem include specific ranges for x and n, highlighting the importance of handling edge cases in the solution.

Problem 58:Kth Largest Element in a Stream [Amazon]

Technology Made Simple • 79 implied HN points • 29 Sep 22
🕹 Technology Coding Recursion Binary Trees
  1. Problem involves finding the kth largest element in a stream, not the kth distinct element.
  2. The 'KthLargest' class has methods to initialize the object with 'k' and a stream of integers, and to add integers to the stream and return the kth largest element.
  3. Constraints include bounds on 'k', the length of the array, and the values in the array, with at most 10^4 calls to the 'add' method.
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Problem 80: Unique Paths[Google]

Technology Made Simple • 39 implied HN points • 23 Mar 23
🕹 Technology Coding Dynamic Programming Recursion
  1. The problem discussed in the post is about finding unique paths in a grid using dynamic programming and recursion.
  2. The example solutions provided in the post illustrate how a robot can navigate from the top-left corner to the bottom-right corner in different grid sizes.
  3. The author also shares personal information about being a university student seeking work post-graduation and invites readers to check out their resume and LinkedIn profile.

[Solution]Problem 56:Climbing Stairs[Amazon]

Technology Made Simple • 79 implied HN points • 16 Sep 22
🕹 Technology Dynamic Programming Logic Recursion Math
  1. The post discusses a solution for the climbing stairs problem with dynamic programming, logic, recursion, and math.
  2. The problem involves finding the number of distinct ways to climb to the top of a staircase by either taking 1 or 2 steps at a time.
  3. The post provides examples and constraints for the problem, along with a link to test the solution on Leetcode.

The Recursive Function Template[Technique Tuesdays]

Technology Made Simple • 59 implied HN points • 12 Oct 22
🕹 Technology Coding Recursion Interviews Tutoring Software
  1. The recursive function template provides a step-by-step guide to solving recursive problems, helping you avoid overwhelm and work through coding challenges smoothly.
  2. The template includes key components like checking termination cases, processing outcomes, handling recursive cases, and resetting side effects, making problem-solving structured and manageable.
  3. Isolating recursion into helper functions improves code organization, and future Technique Tuesdays may cover the power of helper functions in depth.

Problem 56:Climbing Stairs[Amazon]

Technology Made Simple • 59 implied HN points • 15 Sep 22
🕹 Technology Dynamic Programming Logic Recursion Math
  1. The post discusses a problem related to climbing stairs, involving dynamic programming, logic, recursion, and math.
  2. The problem presents a scenario where you can climb a certain number of steps to reach the top, and you have to find the distinct ways to do so.
  3. Examples and constraints are given, along with a link to test your solution on Leetcode.

Transfinite recursive constructions

Infinitely More • 23 implied HN points • 19 Mar 23
🔬 Science Mathematics Recursion
  1. Recursions can express fundamental relations in various contexts like mathematical sequences and modelings like the Fibonacci sequence.
  2. Many familiar arithmetic functions can be defined by recursion, showing a deeper fundamental aspect of their operations.
  3. Defining functions by recursion can be legitimate for natural numbers, but may fail for real numbers due to multiple or no solutions.

[Solution]Problem 60:N Queens [FAANG+ everyone else]

Technology Made Simple • 39 implied HN points • 14 Oct 22
🕹 Technology Backtracking Recursion Chess
  1. The problem of placing n queens on an n x n chessboard without them attacking each other is known as the n-queens puzzle.
  2. Backtracking and recursion are commonly used strategies for solving the n-queens puzzle.
  3. Solutions to the n-queens puzzle involve distinct board configurations with 'Q' representing a queen and '.' representing an empty space.

Problem 59:Invert Binary Tree [Google]

Technology Made Simple • 39 implied HN points • 06 Oct 22
🕹 Technology Recursion Trees Coding Programming
  1. Inverting a binary tree is a classic problem that demonstrates important concepts like recursion and trees.
  2. This problem can help build a strong foundation for tackling more complex coding challenges involving recursion, trees, graphs, and dynamic programming.
  3. The process of inverting a binary tree involves swapping left and right children recursively starting from the root.

[Solution]Problem 38: Power Function[Stripe]

Technology Made Simple • 39 implied HN points • 20 May 22
🕹 Technology Math Logic Optimization Recursion
  1. The problem focuses on implementing a power function without using built-in functions, showcasing the importance of base mathematical operations.
  2. Starting with a simple brute-force solution can lead to more efficient solutions and impress interviewers by demonstrating a structured problem-solving approach.
  3. Optimizations can be made by leveraging mathematics to improve the linear time complexity of the solution.

Problem 38: Power Function[Stripe]

Technology Made Simple • 39 implied HN points • 19 May 22
🕹 Technology Math Logic Optimization Recursion
  1. The post discusses implementing a power function that calculates x raised to the power n without using built-in functions, focusing on math, logic, optimization, and recursion.
  2. Examples of the power function implementation are provided with input-output pairs to demonstrate how it should work.
  3. There is a special request for feedback and sharing of topics for future focus, along with encouragement to explore additional content and subscribe for further tips and assistance.

Recursive Leap of Faith [Technique Tuesdays]

Technology Made Simple • 39 implied HN points • 18 May 22
🕹 Technology Programming Recursion Dynamic Programming Algorithms Software Development
  1. The 'Recursive Leap of Faith' technique is a powerful approach in recursion where we assume our recursive calls will work as expected, simplifying our problem-solving process.
  2. By using the Leap of Faith, we can break down recursive problems into base cases and recursive steps, making it easier to navigate through complex coding challenges.
  3. To master the Recursive Leap of Faith technique, consistent practice is key. Breaking down problems into base cases and making assumptions about recursive calls helps build proficiency over time.

Steps for building Recursive solutions[Technique Tuesday]

Technology Made Simple • 39 implied HN points • 13 Apr 22
🕹 Technology Coding Tutorial Algorithm Recursion Dynamic Programming
  1. Developing recursive solutions involves creating conjectures, working from base cases, and simplifying complex problems into already solved ones.
  2. Starting with a brute force solution is crucial before attempting dynamic programming for optimal solutions.
  3. Building a strong foundation in recursive thinking is key to mastering more complex concepts like dynamic programming.

Recursion- A mathematical perspective [Math Monday]

Technology Made Simple • 39 implied HN points • 12 Apr 22
🚌 Education Math Recursion Proofs Computer Science Problem Solving
  1. Mathematical Induction is a technique for proving statements by starting with a base case and progressing through inductive steps. It forms the foundation for recursion.
  2. Both Mathematical Induction and recursion rely on base cases, operate on discrete domains, and reduce problems to already proven statements. They are like mirror images of each other in problem-solving.
  3. Understanding Mathematical Induction can greatly improve recursion skills as they share similar problem-solving approaches. Practicing PMI questions can enhance recursion proficiency.

Problem #1 Solution

Technology Made Simple • 39 implied HN points • 15 Aug 21
🕹 Technology Coding Recursion
  1. Identifying recursion problems involves going over example cases by hand, which is a helpful practice for debugging and handling edge cases.
  2. This particular problem is marked as medium difficulty but lies at the lower end of the medium spectrum, requiring a solid understanding to tackle effectively.
  3. Engaging in a 7-day free trial subscription can provide access to more detailed solutions and additional content in the post archives.

Problem 37: Word Search[Amazon]

Technology Made Simple • 19 implied HN points • 12 May 22
🕹 Technology Backtracking Recursion Strings Graphs
  1. Next week's topic will introduce the concept of a Recursive Leap of Faith to help with backtracking, dynamic programming, and recursion.
  2. You can test your coding skills with a popular interview question: Leetcode 79. Word Search.
  3. Ensure your code passes Leetcode submissions even if it doesn't match top speeds, and focus on understanding the problem and providing a correct solution.

[Solution]Problem 29: Arranging Coins in Staircase[Netflix]

Technology Made Simple • 19 implied HN points • 18 Mar 22
🕹 Technology Lists Math Dynamic Programming Recursion Coding
  1. The problem involves arranging coins in a staircase with specific row numbers, and the solution focuses on finding the maximum number of complete rows that can be built.
  2. The solution involves analyzing the input (number of coins) and output (number of complete rows), and working through a simple approach using math to determine the complete rows.
  3. To improve the solution further, simplifications can be made to optimize the algorithm, aiming for a faster runtime complexity close to square root of n.

Problem 29: Arranging Coins in Staircase[Netflix]

Technology Made Simple • 19 implied HN points • 16 Mar 22
🕹 Technology Math Lists Dynamic Programming Recursion
  1. Optimal solutions in coding interviews can impress interviewers and require O(1) time and space complexity.
  2. In a coding problem like this one involving arranging coins in a staircase, understanding the complete rows and incomplete rows is key to solving it.
  3. Preparation for coding interviews, like practicing on Leetcode, can help in tackling similar problems and improving problem-solving skills.

[Solution]Problem 23: Maximize coin collecting[Zillow]

Technology Made Simple • 19 implied HN points • 03 Feb 22
🕹 Technology Recursion Dynamic Programming
  1. Understand and identify the recursive nature of a problem before moving on to find solutions.
  2. Recognize and handle terminal cases effectively, such as stopping at the bottom-right corner and dealing with cells in the last row or column.
  3. Optimize solutions by applying techniques like memoization in dynamic programming to store and reuse calculated values.
  4. Tip: Lead an interviewer to show understanding even if it's a complex problem with an exponential runtime solution.

[Solution]Problem 19: Help Couples sit together [Spotify]

Technology Made Simple • 19 implied HN points • 06 Jan 22
🕹 Technology Recursion Combinatorics Optimization
  1. Creating a brute force solution can guide towards an optimal solution, but in interviews, it's better to showcase understanding and move on to more effective approaches
  2. Greedy algorithms are straightforward and choose the best option at each step, making them applicable for optimization problems like arranging couples
  3. Optimal algorithms, like the greedy approach, can be efficient because they make choices based on immediate benefit, even though they may overlook long-term gains

Problem 18: Pack Words on Board [Google]

Technology Made Simple • 19 implied HN points • 29 Dec 21
🚌 Education Coding Problem Solving Recursion Words
  1. Given a matrix of letters and a dictionary of words, find the maximum number of words that can be constructed from the matrix based on specific rules.
  2. To pack a word on the board, it must be in the dictionary, created from available letters, and have adjacent letters (vertically and horizontally).
  3. In the example, the function should return 3 for the words 'eat, 'in', and 'rat' as valid words that can be formed without touching each other.

[Solution]Problem 7: Merge Binary Trees [Salesforce]

Technology Made Simple • 19 implied HN points • 01 Oct 21
🕹 Technology Programming Interviews Recursion Algorithms Coding
  1. When solving tree problems recursively, finding the base cases first helps in organizing the solution and demonstrates a structured problem-solving approach to the interviewer.
  2. Merging two binary trees involves summing up corresponding nodes from input trees and creating a new tree based on the sum values.
  3. The time complexity of merging two binary trees recursively is O(m+n), where m and n are the number of nodes in each of the input trees.