Dynamic Programming: Coin Change Problem #322

✅ Day 56 of 100 Days LeetCode Challenge Problem: 🔹 #24 – Swap Nodes in Pairs 🔗 https://lnkd.in/g6W2b3Fq Learning Journey: 🔹 Today’s problem focused on swapping every two adjacent nodes in a linked list. 🔹 I used an iterative pointer manipulation approach to swap nodes in pairs without modifying node values. 🔹 A prev pointer helped connect previously swapped pairs with the current pair. 🔹 Careful handling of edge cases (empty list or single node) ensured correctness. Concepts Used: 🔹 Linked List Manipulation 🔹 Pointer Rewiring 🔹 Iterative Traversal 🔹 In-place Modification Key Insight: 🔹 Linked list problems often rely entirely on precise pointer updates. 🔹 Keeping track of previous connections prevents breaking the list structure. 🔹 Drawing pointer transitions step-by-step makes implementation much easier. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

✅ Day 46 of 100 Days LeetCode Challenge Problem: 🔹 #91 – Decode Ways 🔗 https://lnkd.in/gpZQshBr Learning Journey: 🔹 Today’s problem focused on counting the number of ways to decode a numeric string into letters. 🔹 I used a Dynamic Programming approach with space optimization, tracking only the previous two states. 🔹 At each step, I checked both single-digit and two-digit decoding possibilities. 🔹 Careful handling of edge cases like leading zeros was essential to ensure valid decoding paths. Concepts Used: 🔹 Dynamic Programming 🔹 Space Optimization 🔹 String Parsing 🔹 State Transition Key Insight: 🔹 Many decoding problems depend on evaluating valid transitions from previous states. 🔹 Maintaining only necessary previous results reduces space complexity to O(1). 🔹 Edge cases involving zeros are critical in avoiding invalid combinations. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

✅ Day 61 of 100 Days LeetCode Challenge Problem: 🔹 #260 – Single Number III 🔗 https://lnkd.in/gKWtdDrb Learning Journey: 🔹 Today’s problem focused on finding the two elements that appear only once in an array where all others appear twice. 🔹 I used a frequency counting approach with Counter to track occurrences. 🔹 Then, I iterated through the dictionary and collected elements with frequency equal to 1. 🔹 This straightforward method ensures correctness with clear logic. Concepts Used: 🔹 Hash Map / Dictionary 🔹 Frequency Counting 🔹 Array Traversal 🔹 Filtering Logic Key Insight: 🔹 Hash-based counting simplifies duplicate detection problems. 🔹 When constraints allow extra space, clarity can be prioritized over bit-level optimization. 🔹 This problem also has an advanced XOR-based O(1) space solution, but counting keeps the implementation simple and readable. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

✅ Day 47 of 100 Days LeetCode Challenge Problem: 🔹 #152 – Maximum Product Subarray 🔗 https://lnkd.in/gcKQWrHz Learning Journey: 🔹 Today’s problem focused on finding the maximum product of a contiguous subarray. 🔹 Unlike sum-based problems, negative numbers can flip the result, so I tracked both maximum and minimum products at each step. 🔹 Whenever a negative number appeared, I swapped the current max and min to maintain correctness. 🔹 This allowed me to dynamically update the best possible product while traversing the array once. Concepts Used: 🔹 Dynamic Programming 🔹 Kadane-like Optimization 🔹 Greedy State Tracking 🔹 Array Traversal Key Insight: 🔹 Keeping track of both maximum and minimum products is essential due to sign changes. 🔹 Negative numbers can turn the smallest product into the largest. 🔹 Maintaining rolling states leads to an efficient O(n) solution. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

✅ Day 55 of 100 Days LeetCode Challenge Problem: 🔹 #55 – Jump Game 🔗 https://lnkd.in/gnUUqSxm Learning Journey: 🔹 Today’s problem focused on determining whether we can reach the last index of an array given maximum jump lengths at each position. 🔹 I used a greedy approach, tracking the maximum reachable index while traversing the array. 🔹 If at any point the current index exceeds the maximum reachable position, it means the end cannot be reached. 🔹 Otherwise, I continuously update the furthest reachable index. Concepts Used: 🔹 Greedy Algorithm 🔹 Array Traversal 🔹 Reachability Tracking 🔹 Optimization Strategy Key Insight: 🔹 Instead of exploring all paths, tracking the furthest reachable index is sufficient. 🔹 Greedy decisions at each step can guarantee a global solution in certain problems. 🔹 Efficient state tracking reduces the need for dynamic programming. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

✅ Day 54 of 100 Days LeetCode Challenge Problem: 🔹 #728 – Self Dividing Numbers 🔗 https://lnkd.in/gxraQJ82 Learning Journey: 🔹 Today’s problem focused on identifying numbers that are divisible by each of their digits. 🔹 For every number in the given range, I extracted its digits and checked divisibility conditions. 🔹 Any number containing zero was immediately rejected since division by zero is invalid. 🔹 Valid numbers were collected into the final result list. Concepts Used: 🔹 Digit Extraction 🔹 Modulo Arithmetic 🔹 Iterative Checking 🔹 Conditional Filtering Key Insight: 🔹 Breaking numbers into digits simplifies many number-theory problems. 🔹 Early elimination (like handling zeros) improves efficiency. 🔹 Clear validation logic makes implementation straightforward and readable. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity

💻 Project Overview The calculator: Takes two numbers as input from the user Asks the user to select an operator (+, -, *, /) Displays the result with a clear operation label Allows the user to continue calculations until they choose to exit 🧠 What I Learned How to structure a reusable function Writing clean conditional logic Improving user interaction in console applications Thinking logically to handle edge cases 📌 Why This Project Matters Even small projects like this are powerful for building strong programming fundamentals. Mastering the basics is the first step toward building larger, real-world applications. I’m continuously improving my Python skills and working on more hands-on projects. #Python #Programming #Coding #BeginnerProject #SoftwareDevelopment #LearningJourney #Tech

Have you ever wondered how difficult it would be to design and implement a simple compiled programming language completely from scratch - no parsing libraries, no LLVM for code generation (though I'll allow myself off-the-shelf assemblers and linkers)? I have. It's something I've been thinking about for a long time, and now I finally have enough time to actually try it. So here it is: a super simple, yet Turing complete, compiled programming language. It's loosely inspired by Rust, but it lacks most of Rust's features. The documentation is coming soon. As for performance — it's pretty bad. I'm missing virtually every code generation optimization you'd get from LLVM. But hey, it’s still faster than #Python. #Rust https://lnkd.in/gnN5hdWm

Precision and logic are at the heart of every great application. 🔢 I recently developed a Simple Calculator project, focusing on creating a clean interface and robust arithmetic logic. This project was a fantastic way to practice Python functions and error handling to ensure every calculation is accurate and user-friendly. Check out the demo video below to see it in action! 🔗 GitHub Repository: https://lnkd.in/g8rrigDe #SoftwareEngineering #Coding #ProgrammingLogic #CalculatorProject #WebDevelopment #TechSkills

✅ Day 44 of 100 Days LeetCode Challenge Problem: 🔹 #3713 – Longest Balanced Substring 🔗 https://lnkd.in/gfryNgam Learning Journey: 🔹 Today’s problem focused on finding the longest substring where all characters appear with equal frequency. 🔹 I explored all possible substrings by fixing a starting index and expanding the window step by step. 🔹 A frequency array helped track character counts along with the number of distinct characters and maximum frequency. 🔹 By validating whether all active characters share the same count, I identified balanced substrings efficiently. Concepts Used: 🔹 String Processing 🔹 Frequency Counting 🔹 Nested Traversal 🔹 Sliding Window Concepts Key Insight: 🔹 Balanced substring problems rely on maintaining strict frequency conditions. 🔹 Tracking distinct characters and maximum frequency simplifies validation logic. 🔹 Smart bookkeeping can make brute-force approaches effective for constrained problems. #LeetCode #DataStructures #Algorithms #CodingInterview #SoftwareEngineering #SoftwareDeveloper #ProblemSolving #Programming #ComputerScience #TechCareers #100DaysOfCode #DailyCoding #Consistency #LearningInPublic #Python #BackendDevelopment #InterviewPreparation #TechCommunity