Sliding Window + Frequency Maps for Anagram Detection

Problem: Given a binary tree, determine if it is height-balanced, meaning for every node: |height(left) - height(right)| ≤ 1 Key Insight: Instead of calculating height repeatedly (which leads to O(N²)), we can compute height + balance check together in one DFS traversal, achieving O(N) time complexity. Optimal Strategy: 1.Use postorder traversal (bottom-up) 2.Return -1 immediately if any subtree is unbalanced 3.Otherwise, return the height of the subtree Why this matters? This pattern is widely used in: Tree Height problems Diameter of Binary Tree Maximum Path Sum Balanced Tree checks #Python #ProblemSolving

LeetCode Problem 73: "Set Matrix Zeroes": Given an m x n integer matrix matrix, if an element is 0, set its entire row and column to 0's. You must do it in place. The below implementation in Python successfully resolves this problem in optimal way with constant space complexity. The logic is quite straightforward, use the first row and column as markers to determine whether the row or column contains zero inside or not. But before this traverse the first row and column to check whether they contain zeroes or not, store this result in a boolean variable. Now based on markers make the values of corresponding cells as zero. Time Complexity: O(m*n) #DSA #LeetCode #Python #OptimalSolution #Matrix #CompetitiveProgramming #ProblemSolving #CodingChallenge #Algorithms #Logic #DataStructures

🧠 LeetCode Insight — Minimum Size Subarray Sum (Sliding Window) I’ve been spending time strengthening my understanding of common problem-solving patterns, and today I revisited a great example of the sliding window technique. Problem: Find the minimal length of a contiguous subarray whose sum is at least a given target. 💡 Key Idea Instead of checking all possible subarrays, we: Expand the window by moving the right pointer Shrink the window from the left as soon as the sum meets the condition Keep track of the smallest valid window length This ensures we never do unnecessary work. Python CODE: https://lnkd.in/gErMBvjV ⏱ Complexity Time: O(n) Space: O(1) 🎯 Takeaway What clicked for me here is that sliding window problems are really about finding the right moment to shrink the window. Once the condition is satisfied, shrinking early helps discover the optimal answer. 👉 Which sliding window problem helped you understand this pattern better? #Python #DataStructures #ProblemSolving #SlidingWindow #LeetCode #SoftwareEngineering #LearningInPublic

LeetCode Problem 349: "Intersection of two Arrays": Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique and you may return the result in any order. The below implementation in Python resolves this problem efficiently. Time Complexity: O(n) Space Complexity: O(n) Approach: Store the unique values of one array and then traverse the second array to find common elements. Increment the value of common element by 1 and append the only elements with value of 1 in hash-map, in this way duplicates can be handled. #DSA #LeetCode #Python #CompetitiveProgramming #Arrays #Hashing #OptimalSolution #DataStructures #Algorithms #ProblemSolving

I recently implemented the Fourier series representation of a square wave in Python and visualized how the waveform evolves as more harmonics are added. Through this exercise, I clearly understood the role of even symmetry, half-wave symmetry, and quarter-wave symmetry in simplifying Fourier series. Since the signal is even and exhibits half-wave symmetry, the series contains only cosine terms with odd harmonics. A key takeaway for me was observing that at N = 9701 harmonics, the reconstructed signal almost perfectly matches the ideal square wave, vividly demonstrating convergence and the Gibbs phenomenon near discontinuities. This hands-on implementation really strengthened my intuition behind Fourier series beyond the equations—seeing theory turn into a waveform was incredibly rewarding. 📈 Implemented using Python, NumPy, and Matplotlib. Project Link: https://lnkd.in/dXJuAd8y #FourierSeries #SignalProcessing #DSP #SignalsAndSystems #Python #NumericalMethods #Engineering #AppliedMathematics #LearningByDoing #GibbsPhenomenon #STEM

📅 Winter Arc | Task 6/30 🎯 Challenge: Python Today’s focus: **Day 6: Loops Basics** ✅ What I worked on today: (You can personalize these points) - {{Practiced star and number patterns using for + while loops together in Python.}} - {{Learned to combine for and while loops in a single program: for loop to control rows while loop to print stars or numbers in each row}} - {{Wrote patterns like right-angled triangle, inverted triangle, and pyramids using this combined approach.}} 📚 Key takeaways from today: - {{for loops control rows, while loops control printing inside rows.}} - {{Combining loops helps make complex patterns and improves logic skills.}} This journey with Matrix – Winter Arc is helping me stay consistent, sharpen my skills, and take ownership of my daily progress. Small efforts every day are compounding into real growth. Staying locked in. On to the next task ❄️🔥 @MATRIX JEC #MatrixWinterArc #BuildWithMatrix #WinterArc #30DayChallenge #DailyProgress #MatrixJEC

LeetCode | Find Numbers with Even Number of Digits 🔢 🔹 Approaches: • Digit counting using division • String length conversion 🔹 Time Complexity: O(n) 🔹 Space Complexity: O(1) Daily DSA practice to improve logic and consistency 🚀 “We count digits either mathematically or using string length, then check if it’s even.” #LeetCode #DSA #Arrays #Python #CodingJourney #LearningInPublic 

🐍 Did you know that Python closures capture variables, not values? This behavior is called late binding and it can cause surprising results. Example: funcs = [] for i in range(3): funcs.append(lambda: i) # tricky line print([f() for f in funcs]) # [2, 2, 2] Why does this happen? All the lambdas keep a reference to the same variable i. When the loop finishes, i equals 2, so every function returns 2. 💡 We can fix this by forcing early binding using default arguments: funcs.append(lambda i=i: i) This creates a new local variable i for each lambda and stores the current value at definition time. #Python #Closures #ProgrammingTips #LearningInPublic #SoftwareEngineering

Solved "Encode and Decode Strings" (LeetCode 271) The trick? Use a length-prefixed encoding: <length>#<string> For example: ["lint","code"] → "4#lint4#code" Why this works: The length tells the decoder exactly how many characters to read No delimiter conflicts — even if the string itself contains # or digits O(n) time and space A clean example of how a simple idea can handle all edge cases elegantly. #leetcode #dsa #python #problemsolving

Movie Catalog with Python and FastAPI FINAL PROJECT Part 4 -> - models.py , function create_movie updated arguments : instead of a crude dict a model pass trough Pydantic   previous on POST endpoint - Refactor PUT /movies/{movie_id} endput to use MovieUpdate (Pydantic)   previous endpoint updates a existing movie - movies.py update_movie function updated argument: payload: dict -> changes: MovieUpdate - Create model MovieResponse on models.py , use it as response model on all endpoints : GET, POST, PUT, DELETE - create a model of errorResponse   register global handlers #pythonJourney