【代码】C++ //练习 1.20 在网站http://www.informit.com/title/0321714113上，第1章的代码目录中包含了头文件Sales_item.h。将它拷贝到你自己的工作。

【代码】LeetCode //C - 145. Binary Tree Postorder Traversal。

习题 9.8 写一个函数insert，用来向一个动态链表插入结点。

【代码】C++ //习题 4.15 用条件编译方法实现以下功能：输入一行电报文字，可以任选两种输出，一为原文输出；一为将字母变成其下一字母。用#define命令来控制是否要译成密码。

Summary: This solution identifies uncommon words between two sentences, where a word is considered uncommon if it appears exactly once in one sentence and not in the other. The approach involves: Toke

Summary: The problem checks if a deck of cards can be partitioned into groups where each group has the same number of cards (x > 1) and all cards in a group have the same value. Key Insight: The gr

Abstract: The problem requires sorting a deck of cards with unique integer numbers such that, when flipped in sequence according to a specific step (each time the top card is flipped and the next top

Summary: The problem involves determining which words from a given list can be formed using characters from a specified string (each character can be used only once per word). The solution involves co

Abstract: This problem requires calculating the number of valid words corresponding to each puzzle string. A valid word must satisfy two conditions: 1) it contains the puzzle's starting letter; and 2)

Summary: The problem requires finding the maximum length of a substring in string s that can be converted to the corresponding substring in t with a total cost not exceeding maxCost. The cost is calcu