C++11特性

C++17都出来了，是时候整理一波C++11旧特性了。

struct Foo {
    std::string name;
    int age;
};

enum class Options {
    None,
    One,
    All
};

class Person
{
public:
//    Person(int newAge):age(newAge) { std::cout << "Person constructor" << std::endl;}
    int age = 20;
    std::string name = "logan";
    bool isSingle = true;
};

#include <iostream>
#include <string>
#include <vector>
#include <map>

#include "myHeader.h"

using namespace std;


int main(int argc, char **argv)
{
    auto i = 42;
    auto l = 42LL;
    auto p = new Foo();
    cout << "sizeof(i) = " << sizeof(i) << endl;
    cout << "sizeof(l) = " << sizeof(l) << endl;
    cout << "sizeof(p) = " << sizeof(p) << endl;
    cout << "sizeof(*p) = " << sizeof(*p) << endl;
    
    map< string, vector<int> > mymap;
    for (int i = 0; i < 5; i++) {
        string key = string("key") + std::to_string(i);
        vector<int> values;
        for (int j = 0; j < 3; j++) {
            values.push_back(i + j * 10);
        }
        mymap[key] = values;
    }
    
    cout << endl;
    cout << "iterate mymap:" << endl;
    for (auto it = begin(mymap); it != end(mymap); ++it) {
        cout << "key = " << it->first << endl;
        cout << "value = ";
        for (auto iter = begin(it->second); iter != end(it->second); ++iter) {
            cout << *iter << " ";
        }
        cout << endl;
    }
    
    cout << endl;
    cout << "Range-based for loops..." << endl;
    for(const auto &it : mymap) {
        cout << "key = " << it.first << endl;
        cout << "value = ";
        for(const auto &iter : it.second) {
            cout << iter << " ";
        }
        cout << endl;
    }
    
    cout << endl;
    cout << "Strongly-typed enums..." << endl;
    Options myoption = Options::One;
    cout << "my option is: " << static_cast<int>(myoption) << endl;
    
    cout << endl;
    cout << "in-class initialization..." << endl;
    Person xiaoming;
    cout << "age = " << xiaoming.age << endl;
    cout << "name = " << xiaoming.name << endl;
    cout << "isSingle = " << xiaoming.isSingle << endl;
}

参考资料:

C++开发者都应该使用的10个C++11特性

 http://zh.cppreference.com/w/cpp/memory/shared_ptr

http://zh.cppreference.com/w/cpp/memory/weak_ptr