结论:(不妨假设$p_{1}<p_{n}$)$\{p_{i}\}$合法当且仅当$\exists 1\le i\le n-1$,使得$p_{1}\ge p_{i}$且$p_{i+1}\ge p_{n}$ 充分性-- 为了方便,在删除一个元素后,$i$和$n$也随之变化(指向原来的元素,若删除$p_{i}$或$p_{n}$会补充说明) 对$\{p_{1},p_{2},...,p_{i}\}$这个子问题不断删除(直至不能删除),显然最终必然是$p_{1}<p_{2}<...<p_{i}$…

题目简述 The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNA…

题目: The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAP…

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSII…

题目描述: Binary Tree Zigzag Level Order Traversal AC Rate: 399/1474 My Submissions Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and alternate between).…

称号 The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPL…

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSII…

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSII…

本题也属于层次遍历的变形,不同之处在于其遍历的方法是交替进行的,形成一个ZigZag的曲线形式,如下: 代码如下: struct TreeNode { int val; TreeNode* left; TreeNode* right; TreeNode(int x): val(x), left(NULL),right(NULL) {} }; void Swap(vector<int> &ivec) { ; int len = ivec.size(); ; i < len/; i…

mmp,写完没保存,又得重新写.晚上写了简历,感觉身体被掏空,大学两年半所经历的事,一张A4纸都写不满,真是一事无成呢.这操蛋的生活到底想对我这个小猫咪做什么. 今后要做一个早起的好宝宝~晚起就诅咒自己期末考试考的不会.会的不考. 题目: The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this…