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String Problems (54)

54 problems covering pattern matching, palindromes, anagrams, substrings, and string manipulation techniques.

📄️ Add Strings

LeetCode 415 | Difficulty: Easy

📄️ Buddy Strings

LeetCode 889 | Difficulty: Easy

📄️ Check if One String Swap Can Make Strings Equal

LeetCode 1915 | Difficulty: Easy

📄️ Compare Version Numbers

LeetCode 165 | Difficulty: Medium

📄️ Decode String

LeetCode 394 | Difficulty: Medium

📄️ Determine if Two Strings Are Close

LeetCode 1777 | Difficulty: Medium

📄️ DI String Match

LeetCode 979 | Difficulty: Easy

📄️ Encode and Decode Strings

LeetCode Link

📄️ Evaluate Reverse Polish Notation

LeetCode 150 | Difficulty: Medium

📄️ Find First Palindromic String in the Array

LeetCode 2231 | Difficulty: Easy

📄️ Find Unique Binary String

LeetCode 2107 | Difficulty: Medium

📄️ First Unique Character in a String

LeetCode 387 | Difficulty: Easy

📄️ Group Anagrams

LeetCode 49 | Difficulty: Medium

📄️ Group Shifted Strings

LeetCode Link

📄️ Implement strStr()

LeetCode Link

📄️ Integer to English Words

LeetCode 273 | Difficulty: Hard

📄️ Isomorphic Strings

LeetCode 205 | Difficulty: Easy

📄️ Length of Last Word

LeetCode 58 | Difficulty: Easy

📄️ Longest Common Prefix

LeetCode 14 | Difficulty: Easy

📄️ Longest Happy String

LeetCode 1304 | Difficulty: Medium

📄️ Longest Palindrome

LeetCode 409 | Difficulty: Easy

📄️ Longest Valid Parentheses

LeetCode 32 | Difficulty: Hard

📄️ Maximum Length of a Concatenated String with Unique Characters

LeetCode 1360 | Difficulty: Medium

📄️ Minimum Add to Make Parentheses Valid

LeetCode 957 | Difficulty: Medium

📄️ Minimum Insertion Steps to Make a String Palindrome

LeetCode 1437 | Difficulty: Hard

📄️ Minimum Insertions to Balance a Parentheses String

LeetCode 1648 | Difficulty: Medium

📄️ Most Common Word

LeetCode 837 | Difficulty: Easy

📄️ Multiply Strings

LeetCode 43 | Difficulty: Medium

📄️ Number of Steps to Reduce a Number to Zero

LeetCode 1444 | Difficulty: Easy

📄️ Palindrome Number

LeetCode 9 | Difficulty: Easy

📄️ Palindrome Permutation

LeetCode Link

📄️ Permutations

Permutations of a String

📄️ Ransom Note

LeetCode 383 | Difficulty: Easy

📄️ Reorganize String

LeetCode 778 | Difficulty: Medium

📄️ Reverse Nodes in k-Group

LeetCode 25 | Difficulty: Hard

📄️ Reverse String

LeetCode 344 | Difficulty: Easy

📄️ Reverse String II

LeetCode 541 | Difficulty: Easy

📄️ Reverse Vowels of a String

LeetCode 345 | Difficulty: Easy

📄️ Reverse Words in a String

LeetCode 151 | Difficulty: Medium

📄️ Reverse Words in a String II

LeetCode Link

📄️ Reverse Words in a String III

LeetCode 557 | Difficulty: Easy

📄️ Rotate String

LeetCode 812 | Difficulty: Easy

📄️ Simplify Path

LeetCode 71 | Difficulty: Medium

📄️ Smallest String Starting From Leaf

LeetCode 1030 | Difficulty: Medium

📄️ String Compression

LeetCode 443 | Difficulty: Medium

📄️ String to Integer (atoi)

LeetCode 8 | Difficulty: Medium

📄️ String Without AAA or BBB

LeetCode 1026 | Difficulty: Medium

📄️ Text Justification

LeetCode 68 | Difficulty: Hard

📄️ Valid Anagram

LeetCode 242 | Difficulty: Easy

📄️ Valid Number

LeetCode 65 | Difficulty: Hard

📄️ Valid Palindrome

LeetCode 125 | Difficulty: Easy

📄️ Valid Palindrome II

LeetCode 680 | Difficulty: Easy

📄️ Valid Parentheses

LeetCode 20 | Difficulty: Easy

📄️ Valid Parenthesis String

LeetCode 678 | Difficulty: Medium