Cognizant

Cognizant

American multinational information technology services and consulting company.

4 Rounds ~21 Days Medium
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The Interview Loop

Recruiter Screen (30 min)

Standard fit check, behavioral questions, and resume overview.

Technical Loop (3-4 Rounds)

Deep dive into domain knowledge, coding, and system design.

Interview Question Bank

Backend Engineer • Coding • easy

Write a function to reverse a string in-place without using built-in functions like `StringBuilder.reverse()`.

#Strings #Two Pointers
Practice
Backend Engineer • Coding • medium

Given an array of strings, group the anagrams together.

#Strings #HashMaps
Practice
Backend Engineer • Coding • easy

Write a program to merge two sorted linked lists into a single sorted linked list.

#Linked Lists #Pointers
Practice
Backend Engineer • Coding • easy

Given an array of integers and a target sum, return the indices of the two numbers that add up to the target. (Two Sum)

#Arrays #HashMaps
Practice
Backend Engineer • Coding • medium

Write a Java program to find the first non-repeating character in a string using Java 8 Streams.

#Java 8 #Streams #Strings
Practice
Cloud Engineer • Coding • hard

Given an array of integers, write a function to find the first missing positive integer. It must run in O(n) time and use O(1) auxiliary space.

#Arrays #Optimization #Data Structures
Practice
Data Engineer • Coding • easy

Write a Python function to check if two strings are anagrams of each other. Optimize it for time complexity.

#Python #Strings #Hash Maps
Practice
Data Scientist • Coding • medium

Given a string, write a Python function to find the longest palindromic substring.

#String Manipulation #Dynamic Programming #Two Pointers
Practice
Machine Learning Engineer • Coding • medium

Write a Python function to find the top K frequent elements in an array. Can you optimize it to run in O(N log K) time?

#Python #Heaps #Hash Maps
Practice
Machine Learning Engineer • Coding • easy

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

#Python #Stacks #Strings
Practice
Product Manager • Coding • easy

Given an array of daily stock prices, write an algorithm to find the maximum profit you can achieve from a single buy and sell.

#Logic #Optimization #Arrays
Practice
Software Engineer • Coding • easy

Write a program to find the second highest number in an integer array.

#Arrays #Iteration
Practice
Software Engineer • Coding • medium

Implement an LRU (Least Recently Used) Cache.

#Design #Hash Table #Doubly Linked List
Practice
Software Engineer • Coding • medium

Print the left view of a Binary Tree.

#Binary Tree #Breadth-First Search #Depth-First Search
Practice
Software Engineer • Coding • easy

Detect a cycle in a linked list.

#Linked List #Two Pointers
Practice
Software Engineer • Coding • medium

Find the longest substring without repeating characters.

#Strings #Sliding Window #Hash Table
Practice
Software Engineer • Coding • easy

Find the first non-repeating character in a given string and return its index.

#Strings #Hash Table
Practice
Software Engineer • Coding • easy

Given two strings, write a function to check if they are anagrams of each other.

#Strings #Hash Table
Practice
Software Engineer • Coding • easy

Write a program to reverse a string without using any inbuilt functions like StringBuilder.reverse().

#Strings #Two Pointers
Practice
Software Engineer • Coding • medium

Merge two sorted arrays into a single sorted array without using extra space (if the first array has enough buffer at the end).

#Arrays #Two Pointers
Practice

Difficulty Radar

Based on recent AI-sourced data.

Meet Your Interviewers

The "Standard" Interviewer

Senior Engineer

Focuses on core competencies, system constraints, and clear communication.

Simulate

Unwritten Rules

Think Out Loud

Always explain your thought process before writing code or drawing architecture.

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