There is no published HackWithInfy syllabus — it is a competitive programming contest — but Infosys does publish an official sample set of four problems tagged Easy, Medium, Hard and Complex, and participant reports across 2023–2026 are remarkably consistent. Cover the topics below in order and you have covered what Rounds 1 and 2 actually ask.
Topic map by frequency
| Topic cluster | Typical problems | Where it appears |
|---|---|---|
| Arrays, hashing & simulation | Frequency counts, non-adjacent selection, rotations with prefix sums, tank/capacity simulations | Round 1 easy — almost every year |
| Maths & number theory | Sieve, modular arithmetic, divisibility, base representations, parity arguments | Round 1 easy/medium |
| Greedy & heaps | Pick-the-best-repeatedly with diminishing returns (official sample "Food Stamps"), interval scheduling, K-closest / top-K | Round 1 medium, Round 2 |
| Two pointers & sliding window | Longest valid window, subarray sums, string windows | Round 1 medium |
| Dynamic programming | 1-D/2-D DP, Kadane with modifications (sample "MSS with Swaps"), LIS, grid DP, state-transition DP | Round 1 hard, Round 2 — the deciding topic |
| Graphs & trees | BFS/DFS, shortest paths, components, DP on layered graphs (sample "Complex" problem), tree range queries | Round 1 hard, Round 2 |
| Strings | Rearrangement by frequency, palindromes, bracket sequences with wildcards, string-sequence DP | Round 1 medium/hard |
| Advanced (rare) | Segment trees, bitmask DP, matching / min-cost assignment (sample "Lock & Parity") | Round 2 and finale only |
Frequently reported past problems
Titles that recur in participant write-ups — each is a topic in itself: Dish Selection (non-adjacent picks of one type), Stone Piles (redistribute one pile into two targets), Base Representation Starting With 1, Oil Tank Capacity, Character Frequency Rearrangement, Balanced Bracket Count with Wildcards, Subset XOR, K Closest Points, Longest Increasing Subsequence, Array Rotation with Range Queries. Three of them, with solutions in four languages, are on the previous year questions page.
Skills that are not "topics" but decide ranks
- Reading long statements. HackWithInfy problems are story-wrapped and, as 2026 participants put it, "implementation-heavy" — the trap is in the reading.
- Partial-credit strategy. A brute force that passes the small test cases is worth real marks; submit it before optimising.
- 64-bit awareness. Constraints run to 10⁹ per value and 10⁵ elements — sums overflow 32-bit integers.
- Exact I/O. Multiple test cases per input, one answer per line, no extra prompts.
The PPI that follows a good rank adds SQL, OOP, OS and DBMS basics — see interview questions. The MCQ syllabus of the regular Infosys test (pseudocode, aptitude) is not part of HackWithInfy.