| 1 |
TwoSum |
Java |
easy |
| 2 |
Add Two Numbers |
Java |
medium |
| 3 |
Longest Substring Without Repeating Characters |
Java |
medium |
| 4 |
Median of Two Sorted Arrays |
Java |
hard |
| 5 |
Longest Palindromic Substring |
Java |
medium |
| 7 |
Reverse Integer |
Java |
medium |
| 8 |
String to Integer (atoi) |
Java |
medium |
| 10 |
Regular Expression Matching |
Java |
hard |
| 11 |
Container With Most Water |
Java |
medium |
| 12 |
Integer to Roman |
Java |
medium |
| 13 |
Roman to Integer |
Java |
easy |
| 14 |
Longest Common Prefix |
Java |
easy |
| 19 |
Remove Nth Node From End of List |
Java |
medium |
| 20 |
Valid Parentheses |
Java |
easy |
| 21 |
Merge Two Sorted Lists |
Java |
easy |
| 22 |
Generate Parentheses |
Java |
medium |
| 26 |
Remove Duplicates from Sorted Array |
Java |
easy |
| 28 |
Find the Index of the First Occurrence in a String |
Java |
medium |
| 36 |
Valid Sudoku |
Java |
medium |
| 53 |
Maximum Subarray |
Java |
medium |
| 58 |
Length of Last Word |
Java |
easy |
| 66 |
Plus One |
Java |
easy |
| 69 |
Sqrt(x) |
Java |
easy |
| 70 |
Climbing Stairs |
Java |
easy |
| 88 |
Merge Sorted Array |
Java |
easy |
| 98 |
Validate Binary Search Tree |
Java |
medium |
| 99 |
Recover Binary Search Tree |
Java |
medium |
| 100 |
Same Tree |
Java |
easy |
| 101 |
Symmetric Tree |
Java |
easy |
| 102 |
Binary Tree Level Order Traversal |
Java |
medium |
| 103 |
Binary Tree Zigzag Level Order Traversal |
Java |
medium |
| 104 |
Maximum Depth of Binary Tree |
Java |
easy |
| 107 |
Binary Tree Level Order Traversal II |
Java |
medium |
| 108 |
Convert Sorted Array to Binary Search Tree |
Java |
easy |
| 110 |
Balanced Binary Tree |
Java |
easy |
| 111 |
Minimum Depth of Binary Tree |
Java |
easy |
| 112 |
Path Sum |
Java |
easy |
| 116 |
Populating Next Right Pointers in Each Node |
Java |
medium |
| 117 |
Populating Next Right Pointers in Each Node II |
Java |
medium |
| 118 |
Pascal's Triangle |
Java |
easy |
| 121 |
Best Time to Buy and Sell Stock |
Java |
easy |
| 122 |
Best Time to Buy and Sell Stock II |
Java |
medium |
| 125 |
Valid Palindrome |
Java |
easy |
| 133 |
Clone Graph |
Java |
medium |
| 136 |
Single Number |
Java |
easy |
| 141 |
Linked List Cycle I |
Java |
easy |
| 142 |
Linked List Cycle II |
Java |
medium |
| 155 |
Min Stack |
Java |
medium |
| 169 |
Majority Element |
Java |
easy |
| 189 |
Rotate Array |
Java |
medium |
| 191 |
Number of 1 Bits |
Java |
easy |
| 198 |
House Robber |
Java |
medium |
| 202 |
Happy Number |
Java |
easy |
| 204 |
Count Primes |
Java |
medium |
| 205 |
Isomorphic Strings |
Java |
easy |
| 206 |
Reverse Linked List |
Java |
easy |
| 207 |
Course Schedule |
Java |
medium |
| 208 |
Implement Trie (Prefix Tree) |
Java |
medium |
| 217 |
Contains Duplicate |
Java |
easy |
| 234 |
Palindrome Linked List |
Java |
easy |
| 237 |
Delete Node in a Linked List |
Java |
medium |
| 242 |
Valid Anagram |
Java |
easy |
| 268 |
Missing Number |
Java |
easy |
| 278 |
First Bad Version |
Java |
easy |
| 283 |
Move Zeroes |
Java |
easy |
| 319 |
Bulb Switcher |
Java |
medium |
| 326 |
Power of Three |
Java |
easy |
| 344 |
Reverse String |
Java |
easy |
| 350 |
Intersection of Two Arrays II |
Java |
easy |
| 384 |
Shuffle an Array |
Java |
medium |
| 387 |
First Unique Character in a String |
Java |
easy |
| 392 |
Is Subsequence |
Java |
easy |
| 409 |
Longest Palindrome |
Java |
easy |
| 412 |
Fizz Buzz |
Java |
easy |
| 424 |
Longest Repeating Character Replacement |
Java |
medium |
| 438 |
Find All Anagrams in a String |
Java |
medium |
| 461 |
Hamming Distance |
Java |
easy |
| 509 |
Fibonacci Number |
Java |
easy |
| 551 |
Student Attendance Record I |
Java |
easy |
| 589 |
N-ary Tree Preorder Traversal |
Java |
easy |
| 695 |
Max Area of Island |
Java |
medium |
| 704 |
Binary Search |
Java |
easy |
| 705 |
Design HashSet |
Java |
easy |
| 706 |
Design HashMap |
Java |
easy |
| 724 |
Find Pivot Index |
Java |
easy |
| 746 |
Min Cost Climbing Stairs |
Java |
easy |
| 844 |
Backspace String Compare |
Java |
easy |
| 876 |
Middle of the Linked List |
Java |
easy |
| 1046 |
Last Stone Weight |
Java |
easy |
| 1480 |
Running Sum of 1d Array |
Java |
easy |
| 1839 |
Longest Substring Of All Vowels in Order |
Java |
medium |
| 1943 |
Describe the Painting |
Java |
medium |
| 2160 |
Minimum Sum Of Four Digit Number After Splitting Digits |
Java |
easy |