Remove Boxes
A hard-tier problem at 48% community acceptance, tagged with Array, Dynamic Programming, Memoization. Reported in interviews at Tencent and 2 others.
Remove Boxes is a hard dynamic programming problem that looks deceptively simple. You're given an array of boxes with colors and need to remove consecutive boxes of the same color to maximize points. It shows up in interviews at Tencent, Capital One, and Cisco. The catch: removing a box gives you points equal to the count of consecutive same-colored boxes removed together, which means the order and timing of removals matter enormously. The naive greedy approach fails. Most candidates either time out or get stuck on state representation. If this hits your live assessment and you can't crack the DP formulation, StealthCoder solves it invisible to the proctor.
Companies that ask "Remove Boxes"
Remove Boxes 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 because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround.
Get StealthCoderThe trick is realizing you need to track not just the subarray but also how many matching boxes exist outside it. Standard DP alone isn't enough. The state must capture (left index, right index, count of matching boxes to the right of right index), because removing boxes in the middle might let you extend a chain rightward and multiply your points. Memoization is mandatory here since the state space is large and overlapping subproblems are everywhere. Most first-timers try interval DP without the 'count' dimension and watch their solution fail on medium-sized inputs. The acceptance rate sits at 48%, reflecting how many people skip it or time out. This is the kind of problem where the DP formulation itself is the entire battle. Once you see the state, the recurrence is almost mechanical.
Pattern tags
You know the problem.
Make sure you actually pass it.
Remove Boxes recycles across companies for a reason. It's hard-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 because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Remove Boxes interview FAQ
Is Remove Boxes really asked at FAANG-adjacent companies?+
Yes. It's been reported at Tencent, Capital One, and Cisco. It's less common than two-sum variants, but it signals a company that's testing actual DP depth, not just pattern matching. If you see it in your prep list, don't skip it.
What's the trick everyone misses?+
Forgetting to track the count parameter. Standard interval DP (left, right) fails because the optimal removal order depends on how many matching boxes exist outside the interval. The state must be (left, right, count). Without that dimension, you'll get wrong answers or time out.
How does memoization fit in here?+
The state space is O(n^3) where n is array length, because you track left, right, and count. Without memoization, you'd revisit the same subproblems exponentially. A recursive approach with a dictionary or 3D array memo table is standard. Most optimized solutions use recursion plus memo, not bottom-up DP.
Will I time out if I don't optimize?+
Yes. Brute force without memoization hits exponential time. Even a correct DP solution can time out if you're not careful about state transitions. Keep your memo structure tight and avoid unnecessary loops in the recurrence.
How does this connect to other array and DP problems I've drilled?+
It's harder than standard interval DP because of the extra parameter. If you've mastered burst balloons, this is the next level. The core pattern (optimal substructure over intervals with a twist) shows up in game-theory DP too. The key skill is recognizing when greedy fails and DP states need more dimensions.
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