Sage

1 Largest Rectangle in Histogram Hard 2 Median of Two Sorted Arrays Hard 3 Linked List Cycle Easy 4 Diameter of Binary Tree Easy 5 Count Good Nodes in Binary Tree Medium 6 Design Add and Search Words Data Structure Medium 7 Design Twitter Medium 8 Word Search Medium 9 Pacific Atlantic Water Flow Medium 10 Number of Connected Components in an Undirected Graph Medium 11 Alien Dictionary Hard 12 Palindromic Substrings Medium 13 Unique Paths Medium 14 Distinct Subsequences Hard 15 Gas Station Medium 16 Non-overlapping Intervals Medium 17 Happy Number Easy 18 Counting Bits Easy 19 Two Sum Easy 20 Valid Palindrome Easy 21 Longest Repeating Character Replacement Medium 22 Generate Parentheses Medium 23 Find Minimum in Rotated Sorted Array Medium 24 Remove Nth Node From End of List Medium 25 Reverse Nodes in k-Group Hard 26 Lowest Common Ancestor of a Binary Search Tree Medium 27 Binary Tree Maximum Path Sum Hard 28 K Closest Points to Origin Medium 29 Permutations Medium 30 Number of Islands Medium