DKodeTree 195 | Practice Problems

Practice Problems

DKodeTree 195 is the complete collection, combining all problems from the Roots 25, Trunk 35, Branches 35, Crown 45, Canopy 45, and Bonus 10 sets. Use this view to practice across all topics or create custom combinations.
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Showing 195 problems from DKodeTree 195

	Two Sum			Easy
	Find Pivot Index			Easy
	Valid Parentheses			Easy
	Number of Recent Calls			Easy
	Valid Palindrome			Easy
	Binary Search			Easy
	Contains Duplicate II			Easy
	Relative Sort Array			Easy
	Linked List Cycle			Easy
	Delete Node in a Linked List			Medium
	Binary Tree Level Order Traversal			Medium
	Search in a Binary Search Tree			Easy
	Two Sum II - Input Array is Sorted			Medium
	Invert Binary Tree			Easy
	Rabbits in Forest			Medium
	Linked List Cycle II			Medium
	Count the Number of Fair Pairs			Medium
	Binary Tree Cameras			Hard
	Contains Duplicate III			Hard
	Sort an Array			Medium
	Sort Colors			Medium
	Reverse Linked List			Easy
	Binary Tree Inorder Traversal			Easy
	Binary Tree Postorder Traversal			Easy
	Binary Tree Preorder Traversal			Easy
	N-ary Tree Preorder Traversal			Easy
	N-ary Tree Level Order Traversal			Medium
	Last Stone Weight			Easy
	Subsets			Medium
	Flood Fill			Easy
	Fibonacci Number			Easy
	Number of Common Factors			Easy
	Isomorphic Strings			Easy
	Next Greater Element I			Easy
	Evaluate Reverse Polish Notation			Medium
	Min Stack			Medium
	Path Sum			Easy
	Assign Cookies			Easy
	Valid Sudoku			Medium
	Remove K Digits			Medium
	Majority Element			Easy
	Merge Intervals			Medium
	Design Browser History			Medium
	Remove Duplicate Letters			Medium
	3Sum			Medium
	Find All Anagrams in a String			Medium
	Path Sum II			Medium
	Insert Interval			Medium
	Interval List Intersections			Medium
	Remove Covered Intervals			Medium
	Minimum Number of Arrows to Burst Balloons			Medium
	My Calendar I			Medium
	Design a Food Rating System			Medium
	Replace Non-Coprime Numbers in Array			Hard
	Find the Duplicate Number			Medium
	Two Sum IV - Input is a BST			Easy
	My Calendar II			Medium
	Longest Consecutive Sequence			Medium
	Best Time to Buy and Sell Stock			Easy
	Product of Array Except Self			Medium
	XOR Queries of a Subarray			Medium
	Implement Queue using Stacks			Easy
	Merge Sorted Array			Easy
	Move Zeroes			Easy
	Squares of a Sorted Array			Easy
	First Bad Version			Easy
	Search Insert Position			Easy
	Sqrt(x)			Easy
	Find First and Last Position of Element in Sorted Array			Medium
	Maximum Average Subarray I			Easy
	Subarray Product Less Than K			Medium
	Verifying an Alien Dictionary			Easy
	Largest Number			Medium
	Merge Two Sorted Lists			Easy
	Palindrome Linked List			Easy
	Remove Duplicates from Sorted List			Easy
	Balanced Binary Tree			Easy
	Maximum Depth of Binary Tree			Easy
	Validate Binary Search Tree			Medium
	Kth Largest Element in a Stream			Easy
	Subsets II			Medium
	Find if Path Exists in Graph			Easy
	Min Cost Climbing Stairs			Easy
	Greatest Common Divisor of Strings			Easy
	Matrix Block Sum			Medium
	Subarray Sum Equals K			Medium
	Daily Temperatures			Medium
	Design Circular Queue			Medium
	Backspace String Compare			Easy
	Minimize Maximum Pair Sum in Array			Medium
	Find Peak Element			Medium
	Koko Eating Bananas			Medium
	Search in Rotated Sorted Array			Medium
	Longest Substring Without Repeating Characters			Medium
	Max Consecutive Ones III			Medium
	Intersection of Two Linked Lists			Easy
	Diameter of Binary Tree			Easy
	Lowest Common Ancestor of a Binary Tree			Medium
	Delete Node in a BST			Medium
	Top K Frequent Words			Medium
	Combinations			Medium
	Permutations			Medium
	Island Perimeter			Easy
	Max Area of Island			Medium
	Rotting Oranges			Medium
	House Robber			Medium
	Maximum Units on a Truck			Easy
	Count Days Without Meetings			Medium
	Power of Two			Easy
	Single Number			Easy
	Happy Number			Easy
	Count Primes			Medium
	Corporate Flight Bookings			Medium
	Basic Calculator II			Medium
	Reveal Cards In Increasing Order			Medium
	Container With Most Water			Medium
	Minimum Number of Days to Make m Bouquets			Medium
	Single Element in a Sorted Array			Medium
	Replace the Substring for Balanced String			Medium
	Remove Nodes From Linked List			Medium
	Binary Tree Maximum Path Sum			Hard
	Construct Binary Search Tree from Preorder Traversal			Medium
	Find K Pairs with Smallest Sums			Medium
	Single-Threaded CPU			Medium
	All Paths From Source to Target			Medium
	Combination Sum			Medium
	Clone Graph			Medium
	Number of Closed Islands			Medium
	Minimum Genetic Mutation			Medium
	Network Delay Time			Medium
	Path With Minimum Effort			Medium
	Shortest Path in Binary Matrix			Medium
	Course Schedule			Medium
	Number of Provinces			Medium
	Redundant Connection			Medium
	Greatest Sum Divisible by Three			Medium
	Last Stone Weight II			Medium
	Longest Common Subsequence			Medium
	Unique Paths II			Medium
	Best Time to Buy and Sell Stock II			Medium
	Jump Game			Medium
	Two City Scheduling			Medium
	Design Add and Search Words Data Structure			Medium
	Implement Trie (Prefix Tree)			Medium
	Sum of Prefix Scores of Strings			Hard
	Counting Bits			Easy
	Number Complement			Easy
	Insert Delete GetRandom O(1)			Medium
	Count Unguarded Cells in the Grid			Medium
	Pow(x, n)			Medium
	Unique Length-3 Palindromic Subsequences			Medium
	Basic Calculator			Hard
	Largest Rectangle in Histogram			Hard
	Kth Smallest Element in a Sorted Matrix			Medium
	Sliding Window Maximum			Hard
	Binary Search Tree Iterator			Medium
	Furthest Building You Can Reach			Medium
	Restore IP Addresses			Medium
	N-Queens			Hard
	Sudoku Solver			Hard
	Reconstruct Itinerary			Hard
	Cheapest Flights Within K Stops			Medium
	Find the City with the smallest number of Neighbors at a Threshold distance			Medium
	Path with Maximum Probablity			Medium
	Minimum Cost Path with Edge Reversals			Hard
	Minimum Obstacle Removal to Reach Corner			Hard
	Course Schedule II			Medium
	Is Graph Bipartite?			Medium
	Min Cost to Connect All Points			Medium
	Satisfiability of Equality Equations			Medium
	Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree			Hard
	Combination Sum IV			Medium
	Longest Increasing Subsequence			Medium
	Maximum Subarray			Medium
	Unique Binary Search Trees			Medium
	Best Time to Buy and Sell Stock with Cooldown			Medium
	Edit Distance			Medium
	House Robber III			Medium
	Longest Palindromic Subsequence			Medium
	Minimum Path Cost in a Grid			Medium
	Dungeon Game			Hard
	Max Dot Product of Two Subsequences			Hard
	Jump Game II			Medium
	Candy			Hard
	Maximum XOR of Two Numbers in an Array			Medium
	Prefix and Suffix Search			Hard
	Single Number II			Medium
	Spiral Matrix II			Medium
	Sort Matrix by Diagonals			Medium
	Permutation Sequence			Hard
	Wiggle Sort II			Medium
	Sliding Window Median			Hard
	Critical Connections in a Network			Hard
	Paths in Matrix Whose Sum Is Divisible by K			Hard
	Course Schedule III			Hard