Infosys Coding Interview Questions

Preparing Infosys coding questions helps candidates improve their programming, logical thinking, and problem-solving skills for the Infosys recruitment process. These questions are commonly asked in online coding assessments and technical interviews.

• Covers the most frequently asked Infosys coding questions across Easy, Medium, and Hard difficulty levels.
• Helps candidates prepare for Infosys online coding assessments and technical interview rounds with structured practice.

Easy Coding Questions

• Check if an Array Is Sorted 
• Count Digits in a Number 
• Reverse a String 
• Print First N Fibonacci Numbers 
• Remove Duplicates from Sorted Array 
• Best Time to Buy and Sell Stock (at most one transaction allowed) 
• Two Sum 
• Sentence Palindrome
• Binary Search 
• Program for Armstrong Numbers 
• Convert from Any Base to Decimal
• Binary Representation
• Greatest of Three Numbers 
• Sum of all prime numbers between 1 and N 
• Check if a number is power of another number 
• Common Divisors 
• Perfect Number 
• Check if string is rotated by two places 
• Check if Date Is Valid 
• Longest Common Prefix
• Reverse Integer
• Palindrome Number
• Valid Parentheses
• Add Binary
• Pascal's Triangle
• Move Zeroes
• Valid Anagram
• Missing Number
• Maximum Depth of Binary Tree
• Reverse Digits of a Number
• Find Largest and Smallest Element in an Array
• Find Duplicate Elements in an Array
• Move All Negative Numbers to One Side
• Count Frequency of Elements
• First Non-Repeating Character
• Count Set Bits
• Single Number
• Power of Two
• Sieve of Eratosthenes
• GCD of Two Numbers

Medium Coding Questions

• Subarray with Given Sum 
• Count Frequencies in an Array 
• Merge Two Sorted Arrays
• Longest Palindromic Substring 
• Kadane’s Algorithm (Maximum Subarray Sum) 
• Longest Increasing Subsequence 
• Next Permutation 
• Rotate Array 
• Minimum Platforms 
• House Robber 
• Number of subarrays having sum exactly equal to k 
• Generate Parentheses 
• Majority Element 
• Largest Number formed from an Array 
• Container With Most Water
• Group Anagrams
• Merge Intervals
• Spiral Matrix
• Set Matrix Zeroes
• Kth Largest Element in an Array
• Top K Frequent Elements
• Find Peak Element
• Product of Array Except Self
• Search in Rotated Sorted Array
• String to Integer
• Sort an Array
• Rearrange Array Elements by Sign
• Climbing Stairs
• BFS Traversal
• DFS Traversal
• Binary Tree Traversals
• Validate Binary Search Tree
• Lowest Common Ancestor
• Detect Cycle in Undirected Graph
• Detect Cycle in Directed Graph
• Topological Sort
• Reverse Linked List
• Detect Cycle in Linked List
• Remove Nth Node from End of Linked List
• Merge Two Sorted Linked Lists

Hard Coding Questions

• 0 - 1 Knapsack Problem 
• Longest Common Subsequence 
• Edit Distance 
• Partition Equal Subset Sum 
• Wildcard Pattern Matching 
• Matrix Chain Multiplication 
• Max rectangle 
• Trapping Rain Water
• Regular Expression Matching
• Burst Balloons
• Maximal Rectangle
• Largest Rectangle in Histogram
• Median of Two Sorted Arrays
• N-Queens
• Serialize and Deserialize Binary Tree
• Binary Tree Maximum Path Sum
• Word Ladder
• Dijkstra's Algorithm
• Kruskal's Algorithm
• Diameter of Binary Tree
• Search in a Row-wise and Column-wise Sorted Matrix
• Minimum Window Substring
• Palindrome Partitioning