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摘要： 1. std::string size()函数返回值为string::size_type，用下标时，也用string::size_type作为index的类型#include <iostream>#include <cstdio>#include <string>using namespace std;int main(){ string s = "abc"; cout << s << endl; cin >> s; cout << s << endl; string line; 阅读全文

摘要： 1. 这章谈到了初始化和赋值其实是不同的，这使我想起了构造函数中的普通构造函数，拷贝构造函数，赋值构造函数，详见博文C++中的构造函数与析构函数 string这个类有default constructor，即初始化为"".2. 一个变量在一个程序中能够声明多次，但只能定义一次。3. Nonconst varialbes are extern by default. To make a const variable accessible to other files we must explicitly specify that it is extern.4. There i 阅读全文

摘要： 这一章算是简介。自己写了几个程序。1. main函数的返回值int main(){ //after ./a.out, execute 'echo $?', it will output 7. return 7;}2. 对comment的理解#include <iostream>using namespace std;int main(){ cout << "/*"; cout << "*/"; cout << /* "*/" */";}3. 对输入的理解#inc 阅读全文

摘要： 1. MountMount - Combine the FSes into one namespace. All files accessible in a Unix system are arranged in one big tree, the file hierarchy, rooted at /. These files can be spread out over several devices. The mount command serves to attach the filesystem found on some device to the big file tree.Th 阅读全文