摘要：https://leetcode.com/problems/binary-tree-postorder-traversal/Given a binary tree, return the postorder traversal of its nodes' values.For example:Giv... 阅读全文

摘要：Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; }Populate each next pointe... 阅读全文

摘要：Two elements of a binary search tree (BST) are swapped by mistake.Recover the tree without changing its structure.Note:A solution using O(n) space is ... 阅读全文

摘要：shell"" 保留$,`,\, 换行含义，‘’保留字面值$(), ``用于命令替换算术扩展如 $[1+1]for循环：for Host in host1, host2, host3; do echo $Host; donefor Host in host{1,2,3}; do echo $Host... 阅读全文