๐ Find pair that sums upto K.
๐ First repeating character.
๐ Remove duplicates.
๐ Find Duplicate.
๐ Depth First Search(Preorder,Inorder,Postorder), Breadth First Search (Levelorder) in Binary Tree.
๐ Maximum Subarray.
๐ Invert Binary Tree.
๐ Longest substring without repeating character.
๐ Reverse linked list.
๐ Peak finding (peak index in an mountain array, peak element).
๐ Palindrome linked list.
๐ Longest Palindrome substring (or subsequence).
๐ Get substring index.
๐ Sort a linked list.
๐ Valid binary search tree.
๐ Minimum cost path in matrix.
๐ Balanced binary tree.
๐ Paths in matrix.
๐ Product of array except self.
๐ Jump to last index.
๐ Graph DFS, BFS.
๐ String Subsequences.
๐ Valid Brackets.
๐ Flatten a binary tree.
๐ Lowest common ancestor.
๐ Minimum in rotated sorted array.
๐ Add two linked list.
๐ Way to climb stairs.
๐ Subsets that sum upto k.
๐ Ways to decode.
๐ Remove node from BST.
๐ Array permutations.
๐ Longest Common Subsequence.
๐ Longest Consecutive sequence.
๐ Count sorted vowel strings.
๐ Smallest number after removing k digits.
๐ Merge Intervals.
๐ Insert intervals.
๐ Binary tree max sum.
๐ 0-1 knapsack.
๐ Shortest palindrome.
๐ Coin change.
๐ Word search.
๐ N-queens.
๐ Word ladder.
๐ Longest increasing subsequence.