Find All Groups of Farmland
A medium-tier problem at 75% community acceptance, tagged with Array, Depth-First Search, Breadth-First Search. Reported in interviews at Citrix and 0 others.
Find All Groups of Farmland is a medium-difficulty matrix traversal problem that sits at the intersection of connected-component analysis and coordinate geometry. You're given a 2D grid and need to identify rectangular regions of farmland, then return their boundaries. It's not a common daily grind problem, but Citrix has asked it, and the trick isn't obvious if you're used to the standard DFS island-counting pattern. If this problem hits your live assessment and you freeze on how to extract the bounding box efficiently, StealthCoder solves it in seconds, invisible to the proctor.
Companies that ask "Find All Groups of Farmland"
Find All Groups of Farmland 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. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know.
Get StealthCoderThe naive approach is to run DFS or BFS on every cell you haven't visited, marking each farmland cell and tracking its corners. That works, but it's clunky. The smarter pattern: iterate through the grid once, and whenever you hit an unvisited farmland cell, treat it as the top-left corner of a rectangle. DFS down and right to find the bottom-right corner in one pass, then mark the entire rectangle visited. This way you extract each farmland group in linear time without redundant traversals. The trick is realizing farmland groups are rectangular, not just arbitrary connected components. Most candidates either over-complicate with full DFS or miss that you can jump straight to the bounds. StealthCoder surfaces the rectangle-sweep approach instantly if you're stuck during the live OA.
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Make sure you actually pass it.
Find All Groups of Farmland 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. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Find All Groups of Farmland interview FAQ
Is this just a standard connected-components problem?+
No. Standard island problems count connected regions or label them. This one requires you to extract and return the bounding rectangle of each farmland group. The constraint that groups are rectangular is the key insight that changes the algorithm. Missing that leads to over-engineering.
What's the time complexity and does it matter for the acceptance rate?+
O(m*n) to visit each grid cell once, assuming you mark the entire rectangle visited in one pass. The 75% acceptance rate suggests most people get the logic right but may implement it less elegantly. A clean rectangle-sweep approach is what separates a solid solution from a mediocre one.
How does this relate to other matrix topics I should know?+
It combines Array, DFS, and Matrix skills. The DFS part is the traversal; the Array part is coordinate storage; the Matrix part is grid navigation and boundary tracking. If you're weak on any of those, you'll stumble. It's a good checkpoint problem for matrix fundamentals.
How do I know when I've found the bottom-right corner of a farmland rectangle?+
DFS from the top-left until you hit a boundary or non-farmland cell. The last farmland cell in your depth-first path is your anchor. Since groups are rectangular, you don't need to explore all connected cells, just expand down-right to find the extent.
Why is it asked by Citrix and not FAANG companies?+
It's a solid mid-level matrix problem that tests geometric intuition and clean traversal logic. It's not a daily pattern like merge intervals or LRU cache, so it surfaces less in high-volume tech hiring. Citrix likely uses it to screen for grid manipulation and algorithmic clarity.
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