Is Subsequence
A easy-tier problem at 48% community acceptance, tagged with Two Pointers, String, Dynamic Programming. Reported in interviews at Electronic Arts and 11 others.
Is Subsequence looks simple on the surface, but it's a backdoor screening problem at places like Tesla, Salesforce, and Electronic Arts. You get two strings and need to check if one is a subsequence of the other. The acceptance rate sits just under 49%, which means half the candidates who see this live either overthink it or miss the two-pointer trick entirely. It's the kind of problem that costs you 10 minutes in an assessment when you blank on the pattern. If it shows up during your OA and you freeze, StealthCoder solves it invisible to the proctor in seconds.
Companies that ask "Is Subsequence"
Is Subsequence 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 trap is that subsequence doesn't mean substring. You can skip characters, so 'ace' is a subsequence of 'abcde' because the letters appear in order, not consecutively. Two pointers is the clean way: iterate one string and advance a second pointer only when characters match. You'll see candidates try brute force or dynamic programming first, which wastes time and bloats the solution. The DP angle exists, but it's overkill here. Once you see the two-pointer pattern, the code takes 90 seconds. That's where the 48% acceptance rate lives: candidates who haven't drilled two-pointer logic default to complexity they don't need. If you hit this on an OA you didn't study, StealthCoder is the hedge that surfaces the efficient solution while you're under pressure.
Pattern tags
You know the problem.
Make sure you actually pass it.
Is Subsequence 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. 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.
Is Subsequence interview FAQ
Is this really asked at FAANG-like companies?+
Yes. Tesla, Salesforce, Qualcomm, and Pinterest have all asked it. It's popular as a screening problem because it's easy enough to implement in 5 minutes but hard enough to filter candidates who don't know two pointers. Low difficulty doesn't mean low frequency.
What's the trick I'm probably missing?+
Two pointers. Iterate the target string with one pointer. For each character, advance the other pointer through the source string until you find a match or run out of characters. If you exhaust the source string before matching all targets, it's not a subsequence. It's O(n) and O(1) space.
Why is the acceptance rate only 48% if it's easy?+
Easy difficulty doesn't mean easy for candidates under time pressure. Most who fail either confuse subsequence with substring, try inefficient approaches, or write correct code with off-by-one bugs. The pattern itself is straightforward once you see it.
Should I use dynamic programming?+
No. DP works but it's unnecessary complexity that burns time. Two pointers solves it faster and cleaner. Save DP for harder subsequence problems like 'Longest Common Subsequence'. This one rewards simplicity.
How does this relate to other two-pointer problems?+
It's foundational. Two pointers is the pattern you'll see in merge, partition, and palindrome problems. Master this one first because the logic scales to harder string and array problems you'll face at the same companies asking it.
Want the actual problem statement? View "Is Subsequence" on LeetCode →