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DSA Question Tracker & Breakdowns

112 problems tagged String with full breakdowns.

433problems
32companies
39topics
3languages each

Companies

Amazon80Microsoft79Google76Meta76Apple73Uber64Walmart54Atlassian52Bloomberg51Oracle49Salesforce49Goldman Sachs39TikTok34Netflix32Databricks25LinkedIn24Visa23Anduril21Rippling21Snowflake20Adobe16NVIDIA16DE Shaw14JPMorgan14OpenAI14Pinterest14Capital One12Roblox11Airbnb9Flipkart9Anthropic4Ripple4

Topics

Array 240Hash Table 113String 112Depth-First Search 73Sorting 66Dynamic Programming 65Breadth-First Search 56Math 49Design 46Binary Search 44Greedy 43Tree 41Two Pointers 39Heap 35Stack 32Graph 28Matrix 28Sliding Window 26Binary Tree 23Backtracking 22Bit Manipulation 20Prefix Sum 20Simulation 20Union Find 19Linked List 18Queue 13Trie 12Counting 10Recursion 10Divide and Conquer 9Monotonic Stack 9Ordered Set 9Topological Sort 9Data Stream 8Database 6Enumeration 6Binary Search Tree 5Doubly-Linked List 5Geometry 5
String✕Clear all
3.Longest Substring Without Repeating Characters
Hash TableStringSliding Window
Medium+13▶ Mock
5.Longest Palindromic Substring
StringDynamic Programming
Medium+8▶ Mock
49.Group Anagrams
Hash TableStringSorting
Medium+9▶ Mock
20.Valid Parentheses
StackString
Easy+3▶ Mock
438.Find All Anagrams in a String
Hash TableStringSliding Window
Medium+2▶ Mock
Implement Trie (Prefix Tree)
TrieDesignString
Medium+2▶ Mock
91.Decode Ways
Dynamic ProgrammingString
Medium+4▶ Mock
22.Generate Parentheses
StringDynamic ProgrammingBacktracking
Medium+1▶ Mock
567.Permutation in String
Hash TableTwo PointersString
Medium▶ Mock
981.Time Based Key-Value Store
Hash TableStringBinary Search
Medium+1▶ Mock
14.Longest Common Prefix
ArrayStringTrie
Easy+1▶ Mock
76.Minimum Window Substring
Hash TableStringSliding Window
Hard▶ Mock
79.Word Search
ArrayStringBacktracking
Medium+1▶ Mock
13.Roman to Integer
Hash TableMathString
Easy+1▶ Mock
17.Letter Combinations of a Phone Number
Hash TableStringBacktracking
Medium+1▶ Mock
12.Integer to Roman
Hash TableMathString
Medium▶ Mock
399.Evaluate Division
ArrayStringDepth-First Search
Medium▶ Mock
44.Wildcard Matching
StringDynamic ProgrammingGreedy
Hard▶ Mock
721.Accounts Merge
ArrayHash TableString
Medium▶ Mock
125.Valid Palindrome
Two PointersString
Easy▶ Mock
8.String to Integer (atoi)
String
Medium▶ Mock
2408.Design SQL
ArrayHash TableString
Medium▶ Mock
67.Add Binary
MathStringBit Manipulation
Easy▶ Mock
516.Longest Palindromic Subsequence
StringDynamic Programming
Medium▶ Mock
424.Longest Repeating Character Replacement
Hash TableStringSliding Window
Medium▶ Mock
1143.Longest Common Subsequence
StringDynamic Programming
Medium▶ Mock
751.IP to CIDR
StringBit Manipulation
Medium▶ Mock
6.Zigzag Conversion
String
Medium▶ Mock
127.Word Ladder
Hash TableStringBreadth-First Search
Hard▶ Mock
68.Text Justification
ArrayStringSimulation
Hard▶ Mock
1839.Longest Substring Of All Vowels in Order
StringSliding Window
Medium▶ Mock
796.Rotate String
StringString Matching
Easy▶ Mock
3484.Design Spreadsheet
ArrayHash TableString
Medium▶ Mock
631.Design Excel Sum Formula
ArrayHash TableString
Hard▶ Mock
3043.Find the Length of the Longest Common Prefix
ArrayHash TableString
Medium▶ Mock
2062.Count Vowel Substrings of a String
Hash TableString
Easy▶ Mock
1138.Alphabet Board Path
Hash TableString
Medium▶ Mock
227.Basic Calculator II
MathStringStack
Medium▶ Mock
2484.Count Different Palindromic Subsequences
StringDynamic Programming
Hard▶ Mock
2559.Count Vowel Strings in Ranges
ArrayStringPrefix Sum
Medium▶ Mock
2353.Design a Food Rating System
ArrayHash TableString
Medium▶ Mock
2296.Design a Text Editor
Linked ListStringStack
Hard▶ Mock
588.Design In-Memory File System
Hash TableStringDesign
Hard▶ Mock
1396.Design Underground System
Hash TableStringDesign
Medium▶ Mock
115.Distinct Subsequences
StringDynamic Programming
Hard▶ Mock
72.Edit Distance
StringDynamic Programming
Medium▶ Mock
271.Encode and Decode Strings
ArrayStringDesign
Medium▶ Mock
32.Longest Valid Parentheses
StringDynamic ProgrammingStack
Hard▶ Mock
179.Largest Number
ArrayStringGreedy
Medium▶ Mock
28.Find the Index of the First Occurrence in a String
Two PointersStringString Matching
Easy▶ Mock
1048.Longest String Chain
ArrayHash TableTwo Pointers
Medium▶ Mock
2933.High-Access Employees
ArrayHash TableString
Medium▶ Mock
609.Find Duplicate File in System
ArrayHash TableString
Medium▶ Mock
564.Find the Closest Palindrome
MathString
Hard▶ Mock
1768.Merge Strings Alternately
Two PointersString
Easy▶ Mock
1249.Minimum Remove to Make Valid Parentheses
StringStack
Medium▶ Mock
3090.Maximum Length Substring With Two Occurrences
Hash TableStringSliding Window
Easy▶ Mock
131.Palindrome Partitioning
StringDynamic ProgrammingBacktracking
Medium▶ Mock
1366.Rank Teams by Votes
ArrayHash TableString
Medium▶ Mock
1209.Remove All Adjacent Duplicates in String II
StringStack
Medium▶ Mock
402.Remove K Digits
StringStackGreedy
Medium▶ Mock
767.Reorganize String
Hash TableStringGreedy
Medium▶ Mock
93.Restore IP Addresses
StringBacktracking
Medium▶ Mock
3035.Maximum Palindromes After Operations
ArrayHash TableString
Medium▶ Mock
3387.Maximize Amount After Two Days of Conversions
ArrayStringDepth-First Search
Medium▶ Mock
1639.Number of Ways to Form a Target String Given a Dictionary
ArrayStringDynamic Programming
Hard▶ Mock
1915.Number of Wonderful Substrings
Hash TableStringBit Manipulation
Medium▶ Mock
678.Valid Parenthesis String
StringDynamic ProgrammingStack
Medium▶ Mock
443.String Compression
Two PointersString
Medium▶ Mock
692.Top K Frequent Words
ArrayHash TableString
Medium▶ Mock
71.Simplify Path
StringStack
Medium▶ Mock
737.Sentence Similarity II
ArrayHash TableString
Medium▶ Mock
2380.Time Needed to Rearrange a Binary String
StringDynamic ProgrammingSimulation
Medium▶ Mock
2213.Longest Substring of One Repeating Character
ArrayStringSegment Tree
Hard▶ Mock
332.Reconstruct Itinerary
ArrayStringDepth-First Search
Hard▶ Mock
428.Serialize and Deserialize N-ary Tree
StringTreeDepth-First Search
Hard▶ Mock
2096.Step-By-Step Directions From a Binary Tree Node to Another
StringTreeDepth-First Search
Medium▶ Mock
664.Strange Printer
StringDynamic Programming
Hard▶ Mock
1258.Synonymous Sentences
ArrayHash TableString
Medium▶ Mock
2434.Using a Robot to Print the Lexicographically Smallest String
Hash TableStringStack
Medium▶ Mock
1236.Web Crawler
StringDepth-First SearchBreadth-First Search
Medium▶ Mock
140.Word Break II
ArrayHash TableString
Hard▶ Mock
Valid Anagram
Hash TableStringSorting
Easy▶ Mock
Design Add and Search Words Data Structure
StringDepth-First SearchDesign
Medium▶ Mock
Word Search II
ArrayStringBacktracking
Hard+1▶ Mock
43.Multiply Strings
MathStringSimulation
Medium▶ Mock
65.Valid Number
String
Hard▶ Mock
166.Fraction to Recurring Decimal
Hash TableMathString
Medium▶ Mock
205.Isomorphic Strings
Hash TableString
Easy▶ Mock
243.Shortest Word Distance
ArrayString
Easy▶ Mock
244.Shortest Word Distance II
ArrayHash TableTwo Pointers
Medium▶ Mock
257.Binary Tree Paths
StringBacktrackingTree
Easy▶ Mock
282.Expression Add Operators
MathStringBacktracking
Hard▶ Mock
340.Longest Substring with At Most K Distinct Characters
Hash TableStringSliding Window
Medium▶ Mock
383.Ransom Note
Hash TableStringCounting
Easy▶ Mock
387.First Unique Character in a String
Hash TableStringQueue
Easy▶ Mock
394.Decode String
StringStackRecursion
Medium▶ Mock
642.Design Search Autocomplete System
StringDepth-First SearchDesign
Hard▶ Mock
657.Robot Return to Origin
StringSimulation
Easy▶ Mock
696.Count Binary Substrings
Two PointersString
Easy▶ Mock
838.Push Dominoes
Two PointersStringDynamic Programming
Medium▶ Mock
1055.Shortest Way to Form String
Two PointersStringBinary Search
Medium▶ Mock
1087.Brace Expansion
StringBacktrackingBreadth-First Search
Medium▶ Mock
1202.Smallest String With Swaps
ArrayHash TableString
Medium▶ Mock
1297.Maximum Number of Occurrences of a Substring
Hash TableStringSliding Window
Medium▶ Mock
1347.Minimum Number of Steps to Make Two Strings Anagram
Hash TableStringCounting
Medium▶ Mock
1963.Minimum Number of Swaps to Make the String Balanced
Two PointersStringStack
Medium▶ Mock
2232.Minimize Result by Adding Parentheses to Expression
StringEnumeration
Medium▶ Mock
2243.Calculate Digit Sum of a String
StringSimulation
Easy▶ Mock
2914.Minimum Number of Changes to Make Binary String Beautiful
String
Medium▶ Mock
3076.Shortest Uncommon Substring in an Array
ArrayHash TableString
Medium▶ Mock
3078.Match Alphanumerical Pattern in Matrix I
ArrayHash TableString
Medium▶ Mock

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