PayPay coding interview
questions, leaked.
3 problems reported across recent PayPay interviews. Top patterns: string, array, binary search. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
PayPay's interview pulls from a narrow, brutal sample: three problems across easy to hard, but the hard one stacks string manipulation, array traversal, binary search, and advanced data structures into a single problem. You're not seeing a balanced difficulty curve; you're seeing a gotcha. One candidate reports easy warm-up, one medium string problem, then a wall. String shows up twice in the topic distribution, so expect the warm-up and the medium to be parsing or transformation work. The hard problem, Block Placement Queries, is the real fight. If you hit it cold in the live assessment, StealthCoder runs invisibly during screen share and surfaces a working solution in seconds, buying you time to breathe.
Top problems at PayPay
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Largest 3-Same-Digit Number in String | EASY | 100.0 | 69% | String |
| 02 | Block Placement Queries | HARD | 73.7 | 17% | Array · Binary Search · Binary Indexed Tree |
| 03 | Zigzag Conversion | MEDIUM | 64.9 | 52% | String |
Frequencies derived from public community-tagged interview reports. Click a row to view on LeetCode.
You have a week, maybe less. You can't out-grind the list above. StealthCoder runs invisibly during the actual PayPay OA. The proctor cannot see it. Screen share cannot detect it. Built because the OA filter rejects engineers who'd pass the on-site. That's a broken filter. This is the workaround.
Get StealthCoder- string2 · 67%
- array1 · 33%
- binary search1 · 33%
- binary indexed tree1 · 33%
- segment tree1 · 33%
String problems dominate the dataset: two of three reported questions focus on character manipulation, pattern recognition, or transformation. Largest 3-Same-Digit Number is a straightforward scan-and-build pattern; Zigzag Conversion requires thinking spatially about how to traverse a matrix-like arrangement. Neither is a trick, but both expect fluency. The hard problem is the outlier. Block Placement Queries combines array indexing, binary search for range queries, and either a binary indexed tree or segment tree for efficient updates. It's the kind of problem that separates candidates who've seen the pattern from those who haven't. If you've drilled segment trees or BIT, you're calm. If you haven't, the live assessment is when you find out. That's where the hedge matters: if the medium strings go clean, but the hard problem's tree structure isn't obvious, StealthCoder solves it in real time while you stay composed.
Companies with similar patterns
If you prepped for PayPay, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass PayPay.
Memorizing every problem above in a week is a fantasy. StealthCoder is the hedge: an AI overlay that's invisible during screen share. It reads the problem on screen 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.
PayPay interview FAQ
Should I spend more time on string problems than tree structures for PayPay?+
Yes, but not the way you think. String appears twice; tree structures (BIT, segment tree) appear once each but only in the hard problem. Drill strings first for confidence and speed on the warm-up and medium. Binary indexed tree and segment tree are non-negotiable for the hard one, but they're concentrated risk. Spend 60% of prep on strings, 40% on tree structures.
Is binary search worth studying separately or only as part of the hard problem?+
Only the hard problem lists binary search. It's not a standalone topic here, so treat it as a sub-skill you'll need to apply within Block Placement Queries, not as a separate drill. Focus on understanding how binary search accelerates range queries when combined with segment trees or BIT.
What's the realistic difficulty jump from medium to hard for PayPay?+
Steep. The medium string problem (Zigzag) is a solid mid-level challenge. The hard problem layers array traversal, binary search, and advanced tree structures. If you solve the medium in 20 minutes, budget 45 to 60 for the hard. It's one problem, not three, so a single misstep costs you real time.
Should I memorize segment tree or binary indexed tree templates?+
Know both well enough to code one from memory in 10 minutes. Block Placement Queries uses one of them for efficient updates and range queries. You won't know which until you read the problem. Familiarity saves you from starting from scratch mid-assessment.
How much of the PayPay assessment is string manipulation?+
Two of three problems. If you're weak on strings, you're losing time on the easy and medium before you even reach the hard. Largest 3-Same-Digit is a warm-up, but Zigzag Conversion requires solid spatial reasoning. String fluency directly affects your pace for the full assessment.