| ZigZag Conversion |
中等 |
| Regular Expression Matching |
困难 |
| Integer to Roman |
中等 |
| Roman to Integer |
简单 |
| Longest Common Prefix |
简单 |
| Letter Combinations of a Phone Number |
中等 |
| Valid Parentheses |
简单 |
| Generate Parentheses |
中等 |
| Implement strStr() |
简单 |
| Substring with Concatenation of All Words |
困难 |
| Longest Valid Parentheses |
困难 |
| Multiply Strings |
中等 |
| Wildcard Matching |
困难 |
| Group Anagrams |
中等 |
| Length of Last Word |
简单 |
| Valid Number |
困难 |
| Add Binary |
简单 |
| Text Justification |
困难 |
| Simplify Path |
中等 |
| Edit Distance |
困难 |
| Minimum Window Substring |
困难 |
| Scramble String |
困难 |
| Decode Ways |
中等 |
| Restore IP Addresses |
中等 |
| Interleaving String |
困难 |
| Distinct Subsequences |
困难 |
| Valid Palindrome |
简单 |
| Word Ladder II |
困难 |
| Reverse Words in a String |
中等 |
| Compare Version Numbers |
中等 |
| Integer to English Words |
困难 |
| Palindrome Pairs |
困难 |
| Reverse Vowels of a String |
简单 |
| Ransom Note |
简单 |
| Mini Parser |
中等 |
| First Unique Character in a String |
简单 |
| String Compression |
简单 |
| Number of Segments in a String |
简单 |
| Validate IP Address |
中等 |
| Detect Capital |
简单 |
| Longest Uncommon Subsequence I |
简单 |
| Longest Uncommon Subsequence II |
中等 |
| Complex Number Multiplication |
中等 |
| Minimum Time Difference |
中等 |
| Reverse String II |
简单 |
| Construct String from Binary Tree |
简单 |
| Next Greater Element III |
中等 |
| Student Attendance Record I |
简单 |
| Optimal Division |
中等 |
| Delete Operation for Two Strings |
中等 |
| Reverse Words in a String III |
简单 |
| Find the Closest Palindrome |
困难 |
| Tag Validator |
困难 |
| Find Duplicate File in System |
中等 |
| Palindromic Substrings |
中等 |
| Smallest Range |
困难 |
| Valid Parenthesis String |
中等 |
| Valid Palindrome II |
简单 |
| Count Binary Substrings |
简单 |
| Remove Comments |
中等 |
| Count Different Palindromic Subsequences |
困难 |
| Parse Lisp Expression |
困难 |
| Special Binary String |
困难 |
| Basic Calculator IV |
困难 |
| Reorganize String |
中等 |
| Rotated Digits |
简单 |
| Custom Sort String |
中等 |
| Expressive Words |
中等 |
| Ambiguous Coordinates |
中等 |
| String to Integer (atoi) |
中等 |
| Goat Latin |
简单 |
| Masking Personal Information |
中等 |
| Split Array into Fibonacci Sequence |
中等 |
| Shortest Palindrome |
困难 |
| Basic Calculator II |
中等 |
| Shifting Letters |
中等 |
| Score of Parentheses |
中等 |
| To Lower Case |
简单 |
| Longest Substring Without Repeating Characters |
中等 |
| Longest Palindromic Substring |
中等 |
| Repeated String Match |
简单 |
| Repeated Substring Pattern |
简单 |
| Reverse String |
简单 |
| Find and Replace Pattern |
中等 |
| Groups of Special-Equivalent Strings |
简单 |
| Buddy Strings |
简单 |
| Orderly Queue |
困难 |
| Robot Return to Origin |
简单 |
| Count and Say |
简单 |
| Word Subsets |
中等 |
| Most Common Word |
简单 |
| Stamping The Sequence |
困难 |