Delete Characters to Make Fancy String
A easy-tier problem at 72% community acceptance, tagged with String. Reported in interviews at Wayfair and 0 others.
Delete Characters to Make Fancy String is an easy string problem with a 71.6% acceptance rate, and it's been asked at Wayfair. The premise sounds simple: you're deleting characters to satisfy a constraint. But "fancy string" has a specific definition that's easy to misread on the first pass, especially under OA pressure. The problem isn't about finding the shortest result or removing duplicates in the usual sense. It's about understanding what makes a string "fancy" and then figuring out the minimal deletions to get there. If you hit this live and blank on the constraint, StealthCoder surfaces the solution in seconds while the proctor sees nothing.
Companies that ask "Delete Characters to Make Fancy String"
Delete Characters to Make Fancy String 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 Amazon engineer who used it to pass JPMorgan's OA and system design loop.
Get StealthCoderThe trick here is that a fancy string has no three consecutive characters that are the same. You're not optimizing for shortest string or fewest deletions in some complex way. You scan left to right, and whenever you'd create three of the same character in a row, you delete the incoming one. It's a one-pass greedy approach. The common pitfall is overthinking it: trying to decide which character to delete after you've already got three in a row, or building a solution that tracks all possible deletion states. Neither is needed. The greedy scan works because once you've committed to keeping two consecutive identical characters, you have no choice but to reject any third identical character that follows. StealthCoder is the hedge if this exact constraint definition doesn't click during your assessment, letting you move on without derailing.
Pattern tags
You know the problem.
Make sure you actually pass it.
Delete Characters to Make Fancy String recycles across companies for a reason. It's easy-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 Amazon engineer who used it to pass JPMorgan's OA and system design loop. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Delete Characters to Make Fancy String interview FAQ
Is this really an easy problem, or is the wording a trap?+
The 71.6% acceptance rate confirms it's genuinely easy once you understand the constraint. The trap is misinterpreting "fancy string." It doesn't mean unique characters or no adjacent duplicates. It means no three consecutive identical characters. Once that clicks, the solution is a straightforward left-to-right scan.
Do I need dynamic programming or backtracking here?+
No. This is a greedy string problem. Build the result character by character, and reject any character that would create three consecutive identical chars. Single pass, O(n) time, O(n) space. No DP overhead needed.
What's the most common mistake candidates make?+
Trying to delete optimally after the fact, or attempting to track multiple candidate strings. Candidates also sometimes confuse this with "no adjacent duplicates" problems. Remember: exactly three consecutive is the boundary. Two identical in a row is fine.
How does this relate to other string problems?+
It's a close cousin to remove duplicates and remove k-digits problems, but simpler. Those require stacks or complex state tracking. This one is pure greedy iteration. If you've solved remove-duplicates problems, this feels like a lighter variant.
Why has Wayfair asked this, and will other companies?+
It's an easy screen for string fundamentals and greedy thinking. One company on record asked it. Easy problems are often used early in loops or as warm-ups. Seeing it once doesn't predict future frequency, but it's solid interview prep material regardless.
Want the actual problem statement? View "Delete Characters to Make Fancy String" on LeetCode →