String Coding Interview Questions Last Updated : 18 Sep, 2025 Suggest changes Share Like Article Like Report String-related problems often assess a candidate's understanding of concepts like pattern matching, manipulation, and efficient algorithm design. Here is the collection of frequently asked interview questions on Strings. Problems in this Article are divided into three Levels so that readers can practice according to the difficulty level step by step. Easy Problems Palindrome Check Reverse a String Reverse Words Check for RotationFirst Non Repeating Roman to Integer Implement Atoi Encrypt the String – IIEqual Point in Brackets Anagram CheckingPanagram Checking Validate IP Address Add Binary StringsMedium ProblemsInteger to Words Fizz BuzzPalindromic Sentence CheckIsomorphic Strings Check for k-anagram Equal 0,1, and 2Find and replace in String Look and say PatternMinimum repetitions to make SubstringExcel Sheet – IFind the N-th characterNext Palindromic Number with same digitsLength of longest prefix suffixLongest K unique characters substringSmallest window containing all Longest substring without repeating charactersSubstrings of length k with k-1 distinct elementsCount number of substringsInterleaved StringsPrint Anagrams togetherRank the permutationA Special Keyboard Sum of two large numbers Hard ProblemsRepeatedly Remove Duplicates Multiply Two StringsSearch Pattern (KMP-Algorithm)Search Pattern (Rabin-Karp Algorithm) Shortest Common Supersequence Longest substring to form a PalindromeLongest Valid Parenthesis Longest Palindromic Subsequence Distinct Palindromic Substrings Palindrome Substring QueriesNumber of Distinct Subsequences Minimum Deletions for Palindrome Minimum Insertions for Palindrome Max Non-Overlapping Odd Palindrome SumRelated Articles:Array Coding Problems for InterviewsTree Coding Problems for InterviewsGraph Coding Problems for InterviewsDynamic Programming Coding Problems for InterviewsSorting Coding Problems for InterviewsSearching Coding Problems for InterviewsBinary Search Tree Coding Problems for InterviewsRelated Tutorials:DSA TutorialSystem Design Tutorial A abhishek1 Follow Article Tags : Strings DSA GFG Sheets Explore DSA FundamentalsLogic Building Problems 2 min read Analysis of Algorithms 1 min read Data StructuresArray Data Structure 3 min read String in Data Structure 2 min read Hashing in Data Structure 2 min read Linked List Data Structure 2 min read Stack Data Structure 2 min read Queue Data Structure 2 min read Tree Data Structure 2 min read Graph Data Structure 3 min read Trie Data Structure 15+ min read AlgorithmsSearching Algorithms 2 min read Sorting Algorithms 3 min read Introduction to Recursion 14 min read Greedy Algorithms 3 min read Graph Algorithms 3 min read Dynamic Programming or DP 3 min read Bitwise Algorithms 4 min read AdvancedSegment Tree 2 min read Binary Indexed Tree or Fenwick Tree 15 min read Square Root (Sqrt) Decomposition Algorithm 15+ min read Binary Lifting 15+ min read Geometry 2 min read Interview PreparationInterview Corner 3 min read GfG160 3 min read Practice ProblemGeeksforGeeks Practice - Leading Online Coding Platform 6 min read Problem of The Day - Develop the Habit of Coding 5 min read My Profile ${profileImgHtml} My Profile Edit Profile My Courses Join Community Transactions Logout Like