Coding problems

Algorithm problems with tests in Python, JavaScript, Java, Go and C++, checked on our server.

Left, Node, RightStack · Tree · Depth-First SearchEasy Counting Search Tree ShapesTree · Binary Search Tree · MathMedium Is It a Search Tree?Tree · Depth-First Search · Binary Search TreeMedium Two Mixed-Up NodesTree · Depth-First Search · Binary Search TreeMedium Identical TreesTree · Depth-First Search · Breadth-First SearchEasy Mirror-Image TreeTree · Depth-First Search · Breadth-First SearchEasy Tree Rows by DepthTree · Breadth-First Search · Binary TreeMedium Snake Through the Tree LevelsTree · Breadth-First Search · Binary TreeMedium Tree HeightTree · Depth-First Search · Breadth-First SearchEasy Tree From Pre-Order and In-Order WalksTree · Array · Hash TableMedium Tree From In-Order and Post-Order WalksTree · Array · Hash TableMedium Tree Levels From the Bottom UpTree · Breadth-First Search · Binary TreeMedium Balanced Tree from a Sorted ListTree · Binary Search Tree · ArrayEasy Tree From a Sorted ChainTree · Binary Search Tree · Linked ListMedium Evenly Grown TreeTree · Depth-First Search · Binary TreeEasy Nearest Leaf DepthTree · Depth-First Search · Breadth-First SearchEasy Leaf Path With a Given TotalTree · Depth-First Search · Breadth-First SearchEasy All Leaf Paths With a Given TotalTree · Depth-First Search · BacktrackingMedium Tree Into a Right ChainStack · Tree · Depth-First SearchMedium Heaviest Path in a TreeTree · Depth-First Search · Dynamic ProgrammingHard Digit Branch TotalsTree · Depth-First Search · Binary TreeMedium Parent Before ChildrenStack · Tree · Depth-First SearchEasy Children Before ParentStack · Tree · Depth-First SearchEasy Flip a Tree Along Its Left SpineTree · Depth-First Search · Binary TreeMedium The Tree Seen From the RightTree · Depth-First Search · Breadth-First SearchMedium Size of a Packed TreeBit Manipulation · Tree · Binary SearchEasy Mirror the TreeTree · Depth-First Search · Breadth-First SearchEasy K-th Smallest in a Search TreeTree · Depth-First Search · Binary Search TreeMedium Same-Value SubtreesTree · Depth-First Search · Binary TreeMedium Preorder of a Search TreeStack · Tree · Binary Search TreeMedium Routes from Root to LeavesTree · Depth-First Search · StringEasy Nearest Value in a Search TreeTree · Depth-First Search · Binary Search TreeEasy K Keys Nearest to a TargetStack · Tree · Depth-First SearchHard Counting Up Down the TreeTree · Depth-First Search · Binary TreeMedium Tree Columns, Top DownTree · Depth-First Search · Breadth-First SearchMedium Checking a Tree Record With Hash MarksStack · Tree · StringMedium Biggest Search SubtreeTree · Depth-First Search · Binary Search TreeMedium A Party Without Direct BossesTree · Depth-First Search · Dynamic ProgrammingMedium Peel the Leaves Round by RoundTree · Depth-First Search · Binary TreeMedium Left-Hand Leaves TotalTree · Depth-First Search · Breadth-First SearchEasy Downward Chains With a Given TotalTree · Depth-First Search · Binary TreeMedium Remove a Key From a Search TreeTree · Binary Search Tree · Binary TreeMedium Most Frequent Values in a Search TreeTree · Depth-First Search · Binary Search TreeEasy Most Common Subtree TotalTree · Depth-First Search · Hash TableMedium First Value on the Lowest RowTree · Depth-First Search · Breadth-First SearchMedium Largest Value on Each Tree LevelTree · Depth-First Search · Breadth-First SearchMedium Tree From Bracket NotationStack · Tree · Depth-First SearchMedium Add Every Bigger KeyTree · Depth-First Search · Binary Search TreeMedium Longest Path in a TreeTree · Depth-First Search · Binary TreeEasy Tree Outline, CounterclockwiseTree · Depth-First Search · Binary TreeMedium

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