Content 账单里面有 \(n\) 条记录,只有卖出记录和买入记录两种,并且都包含两个信息 \(p_i,q_i\),现在根据这些记录,请执行如下操作: 将所有 \(p_i\) 相等的同种记录合并(就是只能卖出记录和卖出记录合并,买入记录和买入记录合并,不能将卖出记录和买入记录合并). 合并之后,将所有 \(p_i\) 最小的 \(s\) 条卖出记录按照 \(p_i\) 降序输出.将所有 \(p_i\) 最大的 \(s\) 条买入记录按照 \(p_i\) 降序输出. 笔者提醒:买入卖出记录可能…

原题链接在这里:https://leetcode.com/problems/design-log-storage-system/description/ 题目: You are given several logs that each log contains a unique id and timestamp. Timestamp is a string that has the following format: Year:Month:Day:Hour:Minute:Second, for…

BFS基础 广度优先搜索(Breadth First Search)用于按离始节点距离.由近到远渐次访问图的节点,可视化BFS 通常使用队列(queue)结构模拟BFS过程,关于queue见:算法与数据结构基础 - 队列(Queue) 最直观的BFS应用是图和树的遍历,其中图常用邻接表或矩阵表示,例如 LeetCode题目 690. Employee Importance: // LeetCode 690. Employee Importance/* class Employee { publi…

二叉树基础 满足这样性质的树称为二叉树:空树或节点最多有两个子树,称为左子树.右子树, 左右子树节点同样最多有两个子树. 二叉树是递归定义的,因而常用递归/DFS的思想处理二叉树相关问题,例如LeetCode题目 104. Maximum Depth of Binary Tree: // 104. Maximum Depth of Binary Tree int maxDepth(TreeNode* root) { ; +max(maxDepth(root->left),maxDepth(roo…

题目来源 https://leetcode.com/problems/binary-tree-level-order-traversal-ii/ 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). 题意分析 Input: binary tree Output:…

题目来源 https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/ 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). 题意分…

题目来源 https://leetcode.com/problems/binary-tree-level-order-traversal/ Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). 题意分析 Input: 一个二叉树 Output:一个每层数值组合的list Conditions:层次遍历 题目思路 采用…

Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree {3,9,20,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3], [9,20], [15,7] ] co…

题目: 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}, 3 / \ 9 20 / \ 15 7 return its bottom-up level orde…

题目: Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree {3,9,20,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its level order traversal as: [ [3], [9,20], [15,7]…