# Zoho Interview Questions with Answers

8 previously-asked interview questions from Zoho's hiring process, each with the correct answer and a worked explanation. Written against the company's actual test pattern.

_Source: Astra (https://useastra.in). Updated 2026-09-05._

### 1. What is dynamic programming and when is it used?

**Answer:** Dynamic programming solves problems by breaking them into overlapping subproblems and storing their results to avoid recomputation (memoisation or tabulation). It applies when a problem has optimal substructure and overlapping subproblems, such as Fibonacci, knapsack, and longest common subsequence.

**Explanation:** Reuse overlapping subproblem results; needs optimal substructure.

### 2. What is the difference between time complexity and space complexity?

**Answer:** Time complexity measures how the running time grows with input size; space complexity measures how the extra memory grows with input size. Both use Big O notation, and there is often a trade-off between them.

**Explanation:** Time is running-time growth; space is memory growth.

### 3. What is a hash collision and how is it handled?

**Answer:** A collision occurs when two keys hash to the same bucket. It is handled by chaining (a linked list or tree per bucket) or open addressing (probing for the next free slot). A good hash function and load factor keep collisions rare.

**Explanation:** Two keys share a bucket; resolved by chaining or open addressing.

### 4. What is the difference between DFS and BFS?

**Answer:** Depth First Search explores as deep as possible before backtracking, using a stack or recursion, and suits path or connectivity problems. Breadth First Search explores level by level using a queue and finds the shortest path in unweighted graphs.

**Explanation:** DFS goes deep with a stack; BFS goes wide with a queue.

### 5. What is the difference between a compile time error and a runtime error?

**Answer:** A compile time error is detected by the compiler before execution, such as a syntax or type error, and prevents the program from building. A runtime error occurs while the program runs, such as dividing by zero or dereferencing a null pointer.

**Explanation:** Compile time: caught before running. Runtime: happens during execution.

### 6. What is the difference between recursion and iteration?

**Answer:** Recursion solves a problem by calling itself on smaller inputs and uses the call stack, which can be elegant but risks stack overflow. Iteration repeats with loops using constant stack space and is often more efficient. Many problems can be written either way.

**Explanation:** Recursion self-calls (uses the stack); iteration loops (uses less memory).

### 7. Tell me about yourself.

**Answer:** Give a concise 60 to 90 second overview: your degree, key programming strengths, a project you built with its impact, and why Zoho interests you. Zoho values coding ability, so emphasise what you have built.

**Explanation:** Structured pitch; emphasise what you have built.

### 8. Why do you want to join Zoho?

**Answer:** Mention Zoho product engineering culture, its broad suite of software products, the emphasis on strong coding and problem solving over pedigree, and the chance to work on products used worldwide. Tie it to your love of building software.

**Explanation:** Product culture, coding-first, building real products.

More Zoho preparation, including the full recruitment process: https://useastra.in/campus/zoho