第16章 string类和标准模板库

智能指针：在对象被销毁的时候，new的内存也被销毁。不再用delete[]进行释放。

#include<iostream>#include<string>#include<memory> //必须包含的头文件using namespace std;class Report{private:    string str;public:    Report(const string s)    {        str=s;        cout<<"Object is created!\n";    }    ~Report()    {        cout<<"Object is deleted!\n";    }    void comment()    {        cout<<str<<endl;    }};int main(){    {        auto_ptr<Report> ps(new Report("using auto_ptr"));        ps->comment();    }    {        shared_ptr<Report> ps(new Report("using shared_ptr"));        ps->comment();    }    {        unique_ptr<Report> ps(new Report("using unique_ptr"));        ps->comment();    }    return 0;}

STL之vector
1.

#include<iostream>#include<string>#include<vector>using namespace std;int main(){    vector<string>item(5);    cout<<"enter:";    for(int i=0;i<5;i++)        getline(cin,item[i]);    cout<<"the strings are:\n";    for(int i=0;i<5;i++)        cout<<item[i]<<endl;    return 0;}

2.自定义类：

#include<iostream>#include<string>#include<vector>using namespace std;class Review{private:    int rating;    string title;public:    void fillReview();    void showReviw();};void Review::fillReview(){    cout<<"Enter book title:\n";    getline(cin,title);    /*while(title!="q")    {        cout<<"Enter book rating:";        cin>>rating;        cout<<"Enter book title(q to quit):\n";        getline(cin,title);    }*/    cout<<"Enter book rating:";          cin>>rating;    while(cin.get()!='\n') //输入两个属性时 把cin.get()放在最后        continue;}void Review::showReviw(){    cout<<title<<"\t"<<rating<<endl;}

#include<iostream>#include<vector>#include<string>#include"vector.h"using namespace std;int main(){    vector<Review>books;//知识点    cout<<"Book1:\n";    Review r1;    r1.fillReview();    books.push_back(r1);//知识点    cout<<"Book2:\n";    Review r2;    r2.fillReview();    books.push_back(r2);    cout<<"Book3:\n";    Review r3;    r3.fillReview();    books.push_back(r3);    vector<Review>oldlist(books);    int num=books.size();    if(num>0)    {        cout<<"you have entered:\n"<<"Rating\tBook\n";        for(int i=0;i<num;i++)            books[i].showReviw();        cout<<"reshowing:\n"<<"Rating\tBook\n";        vector<Review>::iterator pt;  //知识点        for(pt=books.begin();pt<books.end();pt++)            pt->showReviw();    }    vector<Review>::iterator pt;    books.erase(books.begin()+1,books.begin()+2);    cout<<"after erase:\n";    for(pt=books.begin();pt<books.end();pt++)        pt->showReviw();    books.swap(oldlist);    cout<<"after swap:\n";    for(pt=books.begin();pt<books.end();pt++)        pt->showReviw();    return 0;}

3.迭代器的使用：

#include<iostream>#include<iterator>#include<vector>#include<algorithm>//包含sort的头文件using namespace std;int main(){    int casts[6]={6,7,2,9,4,11};    vector<int>dice(6);    copy(casts,casts+6,dice.begin());    cout<<"dice to be casts\n ";    sort(dice.begin(),dice.end());    ostream_iterator<int,char> out_iter(cout," ");//定义一个输出流迭代器    copy(dice.begin(),dice.end(),out_iter);//将向量的值送到输出流迭代器    cout<<endl;    cout<<"使用显式反转迭代器：\n";    copy(dice.rbegin(),dice.rend(),out_iter);    cout<<endl;    cout<<"使用隐式反转迭代器：\n";    vector<int>::reverse_iterator ri;    for(ri=dice.rbegin();ri!=dice.rend();ri++)        cout<<*ri<<" ";    cout<<endl;    cout<<"排序后：\n";    sort(dice.begin(),dice.end());    copy(dice.begin(),dice.end(),out_iter);    cout<<endl;    return 0;}

插入：

#include<iostream>#include<vector>#include<string>#include<algorithm>#include<iterator>using namespace std;void output(string s){    cout<<s<<" ";}int main(){    string s1[4]={"fine","fish","fashion","fate"};    string s2[2]={"busy","bats"};    string s3[2]={"silly","singers"};    vector<string>words(4);    copy(s1,s1+4,words.begin());    for_each(words.begin(),words.end(),output);    cout<<endl;    //insert    copy(s2,s2+2,back_insert_iterator<vector<string>>(words));    for_each(words.begin(),words.end(),output);    cout<<endl;    copy(s3,s3+2,insert_iterator<vector<string> >(words,words.end()));    for_each(words.begin(),words.end(),output);    cout<<endl;    return 0;}