Cognizant vs IBM Interview Questions
Cognizant lists 29 LeetCode interview questions while IBM lists 115. They share 14 problems — 48% of Cognizant's bank and 12% of IBM's. Focus on the overlap first, then drill into 15 Cognizant-only and 101 IBM-only questions.
Overview
Preparation Strategy
Step 1 — Shared core: Solve the 14 overlapping problems first. These are the highest-yield questions for candidates interviewing at both Cognizant and IBM.
Step 2 — Company-specific depth: Add Cognizant-specific problems like Count Subarrays of Length Three With a Condition, Smallest Value of the Rearranged Number, Fibonacci Number and IBM-specific problems from the exclusive lists below.
Step 3 — Difficulty tuning: IBM skews harder in our data. Budget extra time for Hard problems if you are targeting that company.
Difficulty Comparison
Top Shared Topics
14 Shared Questions
High-priority problems to practice for both Cognizant and IBM.
| Problem | Difficulty |
|---|---|
| Palindrome Number | Easy |
| Two Sum | Easy |
| Longest Palindromic Substring | Medium |
| Remove Duplicates from Sorted Array | Easy |
| Longest Common Prefix | Easy |
| Maximum Subarray | Medium |
| Reverse Integer | Medium |
| Valid Parentheses | Easy |
| Median of Two Sorted Arrays | Hard |
| Longest Substring Without Repeating Characters | Medium |
| Merge Sorted Array | Easy |
| 3Sum | Medium |
| Happy Number | Easy |
| Fizz Buzz | Easy |
Unique to Cognizant (15)
Problems in Cognizant's list that do not appear at IBM.
| Problem | Difficulty |
|---|---|
| Count Subarrays of Length Three With a Condition | Easy |
| Smallest Value of the Rearranged Number | Medium |
| Fibonacci Number | Easy |
| Valid Anagram | Easy |
| Second Highest Salary | Medium |
| Managers with at Least 5 Direct Reports | Medium |
| Product Sales Analysis I | Easy |
| Count Primes | Medium |
| Move Zeroes | Easy |
| Binary Search | Easy |
| Merge Two Sorted Lists | Easy |
| Add Two Numbers | Medium |
Unique to IBM (101)
Problems in IBM's list that do not appear at Cognizant.
Frequently Asked Questions
How many LeetCode questions do Cognizant and IBM share?
Cognizant and IBM share 14 LeetCode interview questions. 15 problems appear only in Cognizant's list and 101 appear only in IBM's list.
What topics overlap most between Cognizant and IBM?
The most common shared topics between Cognizant and IBM are Array (6 shared questions), Two Pointers (5 shared questions), String (5 shared questions), Math (4 shared questions), Hash Table (3 shared questions). Mastering these areas prepares you for both companies.
Which company asks harder LeetCode questions: Cognizant or IBM?
Cognizant has 18 Easy, 10 Medium, and 1 Hard questions. IBM has 33 Easy, 73 Medium, and 9 Hard questions. IBM has a higher proportion of Hard problems in its interview set.
How should I prepare if interviewing at both Cognizant and IBM?
Start with the 14 shared problems since they cover what both companies ask most often. Then add 15 Cognizant-specific and 20 IBM-specific questions to round out your prep.