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Companies
Amazon
String
String
0/159 solved
Longest Substring Without Repeating Characters
MEDIUM
Longest Palindromic Substring
MEDIUM
Valid Parentheses
EASY
Generate Parentheses
MEDIUM
Group Anagrams
MEDIUM
Letter Combinations of a Phone Number
MEDIUM
Longest Common Prefix
EASY
Minimum Window Substring
HARD
Word Break
MEDIUM
Word Search
MEDIUM
Edit Distance
MEDIUM
Roman to Integer
EASY
Longest Common Subsequence
MEDIUM
Palindrome Partitioning
MEDIUM
Decode String
MEDIUM
Longest Valid Parentheses
HARD
Valid Anagram
EASY
Find All Anagrams in a String
MEDIUM
Regular Expression Matching
HARD
Word Ladder
HARD
Decode Ways
MEDIUM
Permutation in String
MEDIUM
Implement Trie (Prefix Tree)
MEDIUM
Longest Repeating Character Replacement
MEDIUM
Partition Labels
MEDIUM
Serialize and Deserialize Binary Tree
HARD
Valid Palindrome
EASY
Longest Palindromic Subsequence
MEDIUM
Remove K Digits
MEDIUM
Add Binary
EASY
Word Search II
HARD
Evaluate Division
MEDIUM
Isomorphic Strings
EASY
First Unique Character in a String
EASY
Largest Number
MEDIUM
Reverse String
EASY
Remove Duplicate Letters
MEDIUM
Reorganize String
MEDIUM
Sort Characters By Frequency
MEDIUM
Wildcard Matching
HARD
Interleaving String
MEDIUM
Zigzag Conversion
MEDIUM
Top K Frequent Words
MEDIUM
Design Add and Search Words Data Structure
MEDIUM
Backspace String Compare
EASY
Integer to Roman
MEDIUM
Word Break II
HARD
Multiply Strings
MEDIUM
Minimum Remove to Make Valid Parentheses
MEDIUM
Accounts Merge
MEDIUM
Distinct Subsequences
HARD
Remove All Adjacent Duplicates In String
EASY
Basic Calculator
HARD
Valid Parenthesis String
MEDIUM
Find the Index of the First Occurrence in a String
EASY
Basic Calculator II
MEDIUM
Word Ladder II
HARD
Reverse Words in a String III
EASY
Remove Invalid Parentheses
HARD
Remove All Adjacent Duplicates in String II
MEDIUM
Simplify Path
MEDIUM
Palindrome Partitioning II
HARD
Length of Last Word
EASY
Greatest Common Divisor of Strings
EASY
String Compression
MEDIUM
Restore IP Addresses
MEDIUM
Minimum Insertion Steps to Make a String Palindrome
HARD
Ransom Note
EASY
Add Strings
EASY
Find the Difference
EASY
Shortest Common Supersequence
HARD
Minimum Deletions to Make Character Frequencies Unique
MEDIUM
String to Integer (atoi)
MEDIUM
Verifying an Alien Dictionary
EASY
Open the Lock
MEDIUM
Search Suggestions System
MEDIUM
Reverse Vowels of a String
EASY
Letter Case Permutation
MEDIUM
Alien Dictionary
HARD
Flip String to Monotone Increasing
MEDIUM
Find Common Characters
EASY
Rotate String
EASY
Count and Say
MEDIUM
Concatenated Words
HARD
Text Justification
HARD
Robot Bounded In Circle
MEDIUM
Integer to English Words
HARD
Maximum Number of Vowels in a Substring of Given Length
MEDIUM
Serialize and Deserialize BST
MEDIUM
Repeated DNA Sequences
MEDIUM
Scramble String
HARD
Minimum Genetic Mutation
MEDIUM
Reverse Substrings Between Each Pair of Parentheses
MEDIUM
Word Subsets
MEDIUM
Compare Version Numbers
MEDIUM
Longest Happy String
MEDIUM
Smallest Subsequence of Distinct Characters
MEDIUM
Repeated String Match
MEDIUM
Decoded String at Index
MEDIUM
Robot Return to Origin
EASY
Break a Palindrome
MEDIUM
Prefix and Suffix Search
HARD
Longest Duplicate Substring
HARD
Find Words That Can Be Formed by Characters
EASY
Reorder Data in Log Files
MEDIUM
Design Search Autocomplete System
HARD
Encode and Decode TinyURL
MEDIUM
Substring with Concatenation of All Words
HARD
Number of Atoms
HARD
Uncommon Words from Two Sentences
EASY
Orderly Queue
HARD
Parsing A Boolean Expression
HARD
Most Common Word
EASY
Remove Palindromic Subsequences
EASY
Recover a Tree From Preorder Traversal
HARD
Decrypt String from Alphabet to Integer Mapping
EASY
Find Duplicate File in System
MEDIUM
Design In-Memory File System
HARD
Path Crossing
EASY
Minimum Window Subsequence
HARD
Find the Shortest Superstring
HARD
One Edit Distance
MEDIUM
Numbers At Most N Given Digit Set
HARD
Iterator for Combination
MEDIUM
Valid Number
HARD
Longest Absolute File Path
MEDIUM
Find the Closest Palindrome
HARD
Minimum Length of String After Deleting Similar Ends
MEDIUM
K-Similar Strings
HARD
Basic Calculator III
HARD
Split Array into Fibonacci Sequence
MEDIUM
Shortest Word Distance II
MEDIUM
Serialize and Deserialize N-ary Tree
HARD
Swap For Longest Repeated Character Substring
MEDIUM
Camelcase Matching
MEDIUM
Word Pattern II
MEDIUM
Alphabet Board Path
MEDIUM
String Matching in an Array
EASY
Sentence Similarity II
MEDIUM
Maximum Number of Non-Overlapping Substrings
HARD
Slowest Key
EASY
Rearrange Words in a Sentence
MEDIUM
Next Closest Time
MEDIUM
Complex Number Multiplication
MEDIUM
Encode String with Shortest Length
HARD
Design File System
MEDIUM
Find K-Length Substrings With No Repeated Characters
MEDIUM
Solve the Equation
MEDIUM
Minimum Possible Integer After at Most K Adjacent Swaps On Digits
HARD
Design Compressed String Iterator
EASY
Vowel Spellchecker
MEDIUM
Count The Repetitions
HARD
Number of Days Between Two Dates
EASY
Index Pairs of a String
EASY
Remove Vowels from a String
EASY
Synonymous Sentences
MEDIUM
Web Crawler
MEDIUM
Build Binary Expression Tree From Infix Expression
HARD
Sort Features by Popularity
MEDIUM