Solved Word Search without DFS or Recursion using Index Tracking

🚀 How I Solved LeetCode’s Word Search Problem Without DFS or Recursion When I came across Word Search (LeetCode 79), I noticed that almost every solution used DFS and backtracking. But I wanted to solve it my own way — using index tracking and adjacency logic instead of recursion. My intuition was simple: If a word exists in the grid, every next letter must lie right next to the previous one — either up, down, left, or right. That means their coordinate difference should satisfy: abs(x1 - x2) + abs(y1 - y2) == 1. This small observation became the foundation of my entire approach. 💡 My Thought Process 1️⃣ I mapped every letter in the grid to its coordinates. 2️⃣ I started from all positions of the first letter in the word. 3️⃣ For every next letter, I checked which positions are adjacent and not already used. 4️⃣ I extended paths step by step — no recursion, only iteration. 5️⃣ If any path reached the last letter → the word exists. ⚙️ My Implementation I used a BFS-style iterative search, where each state holds: the current cell (x, y) the current index in the word and a bitmask representing already-used cells. This replaced recursion and heavy visited[][][] arrays with a compact integer mask. Each move just extended to adjacent cells if the next character matched. It handled tricky cases like "ABCB" perfectly → returned false, which even some DFS implementations fail on. ✅ Why It Worked ✔️ No recursion = no stack overflow. ✔️ Bitmask = minimal memory use. ✔️ Adjacency rule = exactly matches grid movement. ✔️ Iterative BFS = simple, efficient, and logical. 🎯 What I Learned You don’t always need to follow the standard algorithms. Sometimes, just trusting your intuition and building around your idea leads to something even better. This problem taught me that creativity and logic go hand in hand. And when you believe in your approach — it truly works. 💪 #Coding #LeetCode #ProblemSolving #Cplusplus #Innovation #DSA #Learning #DeveloperJourney

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Congratulations 🎉 Sachin on completing LeetCode problem 79, Word Search. This accomplishment reflects great perseverance and deep understanding of algorithms. Such milestones are earned through consistent effort and a passion for problem solving. Your determination to improve with every challenge is inspiring and sets a strong example for others learning to master coding concepts. Keep up the momentum and continue reaching new heights in your technical journey. Well done on this achievement, Sachin!

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