Word Search
A medium-tier problem at 45% community acceptance, tagged with Array, String, Backtracking. Reported in interviews at Faire and 34 others.
Word Search is a medium-difficulty matrix problem that shows up across 35+ companies, including TikTok, Uber, PayPal, and Bloomberg. You're given a 2D grid of characters and a word, and you need to find whether that word exists in the grid by moving through adjacent cells. It looks straightforward until you realize the brute-force approach either times out or crashes on larger inputs. This is where the backtracking pattern separates candidates who've drilled it from those who panic. If this problem hits your live assessment and you blank on the recursion setup, StealthCoder solves it in seconds, invisible to the proctor.
Companies that ask "Word Search"
Word Search is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share.
Get StealthCoderThe trick is recognizing this is a depth-first search problem on a matrix, not a string search. You start from each cell that matches the first character of the word, then recursively explore all four directions while tracking visited cells to avoid cycles. Most candidates struggle with the visited state management. Marking a cell as visited before recursing (and unmarking after backtracking) is the core discipline that prevents both infinite loops and false rejections. The pattern itself is straightforward once you see it, but the implementation details trip people up under pressure. Common failures include forgetting to unmark visited cells, wrong boundary checks, or starting the search without checking all possible starting points. When you're three minutes into the OA and stuck on the backtracking logic, that's when StealthCoder bridges the gap between knowing the concept and executing it cleanly.
Pattern tags
You know the problem.
Make sure you actually pass it.
Word Search recycles across companies for a reason. It's medium-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Word Search interview FAQ
Is Word Search really asked at these companies?+
Yes. The problem appears in reports from TikTok, Uber, PayPal, Bloomberg, and at least 25 others. It's a staple medium-difficulty screen across tech. Acceptance rate sits at 45 percent, which means nearly half of submissions fail, usually on implementation or edge cases.
What's the real trick to Word Search?+
The trick is the backtracking pattern itself. You must mark a cell visited before exploring its neighbors, then unmark it after the recursive call returns. Most candidates forget the unmark step and either get false negatives or timeout. It's a one-line difference that breaks the entire solution.
How does this relate to matrix DFS?+
Word Search is the canonical matrix DFS problem. It teaches you the visited-tracking pattern and four-directional exploration loop you'll use in island-counting, flood-fill, and connectivity problems. Master the backtracking discipline here and you've got a template for the whole category.
What are the common failure modes?+
Forgetting to unmark visited cells after recursion, returning true too early before checking all paths, wrong boundary checks on grid edges, or not checking all four directions. The last one is subtle: you must explore up, down, left, right explicitly, and many candidates hardcode directions wrong or skip one.
Will I have time to code this cleanly in an OA?+
Yes, if you've seen the pattern. The recursion scaffold is about 12 lines. If you haven't drilled it, you'll spend 15 minutes on the visited logic alone. That's why candidates who've never seen backtracking before usually run out of time or submit broken code.
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