47 questions · from 4 interviews
Ciena interview questions
Every question candidates reported from their Ciena interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Ciena coding and DSA questions
- 01
Longest Substring Without Repeating Characters
Given a string, find the length of the longest substring without repeating characters. Example: abcac → abc → Output: 3
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 02
Merge Two Sorted Linked Lists
Given two sorted linked lists, merge them into a single sorted linked list. Example: l1: 1 → 3 → 5, l2: 2 → 4 → 6
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 03
Coin Change Problem
Solve the classic Coin Change problem to find the minimum number of coins needed to make a specific sum.
Medium · From Ciena On Campus || BPS delivery
- 04
Spiral Matrix Traversal
Implement the spiral traversal of a given matrix.
Medium · From Ciena On Campus || BPS delivery
- 05
Array Traversal with Power of Two Condition
Given an array, traverse it and for each element, find the largest power of 2 that is less than or equal to that element.
Easy · From Ciena On Campus || BPS delivery
- 06
DFS and BFS Tree Traversal
Given a tree (drawn on paper), perform Depth-First Search (DFS) and Breadth-First Search (BFS) traversals. Also, identify the data structures commonly used for DFS and BFS.
Easy · From Ciena On Campus || BPS delivery
- 07
Heap with Many Nodes
Discuss the implications if a heap were implemented using a tree with many nodes per level instead of a standard binary tree structure.
Medium · From Ciena On Campus || BPS delivery
- 08
Binary Representation Palindrome
Check if a number's binary representation is a palindrome.
- 09
Students Incorrect Height Order
Given students' heights and their current arrangement, identify and print the indexes of students who are not standing in increasing height order.
- 10
Find Middle of Linked List
Implement a method to find the middle of a linked list. Follow-up: If the linked list has an even number of nodes, what would the current code return, and how can it be configured to handle this?
- 11
Reverse Words in a Sentence
Write code to reverse the order of words in a given sentence.
- 12
Find Duplicate in 1 to N Array
Given an array of n+1 integers where each integer is between 1 and n (inclusive) and there is exactly one duplicate element, find the duplicate. Discuss the time complexity and explain the slow and fast pointer approach (Floyd's Tortoise and Hare).
- 13
Polyfill for `call` method
Implement a polyfill for the native JavaScript call method.
Medium · From Ciena UI Developer
- 14
Count Continuous Characters using Reduce
Write a program using the reduce method that takes a string as input and returns an array of objects, where each object contains a character and its continuous count. For example, if the input is 'aaabbccaa', the output should be '[{a:3}, {b:2}, {c:2},…
Medium · From Ciena UI Developer
Ciena system design questions
- 01
Kafka Basics
Explain the fundamental concepts and architecture of Apache Kafka.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 02
Kafka Partitions and Consumers
Discuss Kafka partitions, their purpose, and how consumers interact with them to process messages.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 03
Handling High Traffic Scenarios
Describe architectural patterns, strategies, and considerations for designing systems that can effectively handle high traffic and scale accordingly.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 04
Deadlock Avoidance Conditions
Explain how to avoid deadlocks by describing the four necessary conditions for deadlock.
- 05
Semaphores vs Mutex
Explain the difference between semaphores and mutexes.
- 06
Purpose of Mutex
Explain the purpose and use cases of mutexes.
Ciena other questions
- 01
Difference between @RestController vs @Controller
Explain the key differences between Spring's @RestController and @Controller annotations.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 02
Create a Sample REST API
Design and outline how to create a sample REST API, possibly using Spring Boot.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 03
Spring Boot Annotations and Application Startup Process
Describe common Spring Boot annotations and explain the internal process of how a Spring Boot application starts up, mentioning all relevant annotations.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 04
Find Second Highest Salary
Write a SQL query to find the second highest salary from a table.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 05
Find Second Highest Unique Salary
Write a SQL query to find the second highest unique salary from a table.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 06
Flip Binary Values in a Table
Given a table BINARYTABLE with a column containing binary values (0 or 1), write a SQL query to flip these values (0 becomes 1, 1 becomes 0). Table: BINARYTABLE 0 1 0
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 07
Java 8 Features (Streams, Collections)
Discuss the significant features introduced in Java 8, specifically focusing on Streams API and enhancements to the Collections framework.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 08
Internal Working of HashMap
Explain the internal data structures and algorithms that power Java's HashMap.
From Ciena SDE-1 Interview Experience (Gurgaon) – Technical Round 1
- 09
Project Discussion & Web Fundamentals
Discuss your most familiar project, including the motivation behind building it. Expect questions on authorization, authentication, API versioning, HTTP status codes (client-side and server-side responses), and how JWT tokens function.
- 10
Thread vs. Process Scheduling
Explain the key differences between thread scheduling and process scheduling in an operating system.
Medium · From Ciena On Campus || BPS delivery
- 11
Code for Threads and Locks
Write code demonstrating the use of threads and locks for synchronization.
Medium · From Ciena On Campus || BPS delivery
- 12
SQL Normalization and Joins
Explain database normalization (e.g., normal forms) and describe different types of SQL joins.
Easy · From Ciena On Campus || BPS delivery
- 13
C++ Dynamic Cast
Explain what 'dynamiccast' is in C++ and its use cases.
Medium · From Ciena On Campus || BPS delivery
- 14
C++ Memory Leak Detection
Describe methods or tools used to detect memory leaks in a C++ program.
Hard · From Ciena On Campus || BPS delivery
- 15
C++ Binary File Processing
Explain how to process a binary file in C++ (e.g., reading/writing binary data).
Medium · From Ciena On Campus || BPS delivery
- 16
C++ Random Number Generator
Describe how to create a random number generator in C++.
Medium · From Ciena On Campus || BPS delivery
- 17
C Function Pointer Syntax
Write the C syntax for a void function pointer that accepts two integer inputs and demonstrate how to assign it to a real function.
- 18
C Malloc Function Details
Explain the malloc syntax and describe what type of value malloc returns.
- 19
Static vs Global Variables
Define static variables and explain the differences between static and global variables in C.
- 20
C Struct Memory Layout and Padding
If a C struct contains two integers and one character, calculate the memory it occupies. Follow-up: Where is the memory padding stored internally?
- 21
C Struct vs Union
Explain the differences between struct and union in C.
- 22
Declaration, Initialization, Definition
Explain the differences between declaration, initialization, and definition for a variable.
- 23
Malloc(0) Behavior
Describe what happens if malloc(0) is called.
- 24
C Pointer Array Declarations
Write the C syntax to declare an array of size 10 that stores pointers to integers, and then declare a pointer to an array of size 10 that stores integers.
- 25
C Pointer Dereference & Increment
Given the C code snippet: int x = 10; int ptr = x; ++(ptr); , what would ptr return?
2 more in the Ciena write-ups.
Ciena interview questions FAQ
What questions are asked in Ciena interviews?
Candidates reported 47 distinct questions across 4 Ciena interviews. 14 coding and DSA questions, 6 system design questions, 27 other questions.
How difficult are Ciena interview questions?
Of the questions candidates rated, 21% were easy, 71% medium and 7% hard.