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Binary Tree Inorder Traversal（二叉树中序遍历）Given a binary tree, return the inorder traversal of its nodes’ values.For example:Given binary tree{1,#,2,3},return[1,3,2].Note: Recursive solution is triv...

题目Binary Tree Preorder TraversalGiven a binary tree, return the preorder traversal of its nodes’ values.For example:Given binary tree{1,#,2,3},return[1,2,3].Note: Recursive solution is trivia...

题目描述Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).For example, this binary tree is symmetric:But the following is not:Note:Bonus points if you co...

题目描述Given a binary tree, return the bottom-up level order traversal of its nodes’ values. (ie, from left to right, level by level from leaf to root).For example:Given binary tree{3,9,20,#,#,15,7},...