C++ primer第4版 4.25

编写程序比较两个 string 类型的字符串，然后编写另一 个程序比较两个 C 风格字符串的值。

    string str1,str2;

    cout<<"Enter two strings:"<<endl;
    cin>>str1>>str2;
    
    if(str1>str2)
        cout<<"""<<str1<<"""<<"is bigger than "<<"""<<str2<<"""<<endl;
    else if(str1<str2)
        cout<<"""<<str2<<"""<<"is bigger than "<<"""<<str1<<"""<<endl;
    else
        cout<<"They are equal"<<endl;

const int str_size = 80;
    char *str1,*str2;

    str1 = new char[str_size];
    str2 = new char[str_size];

    if(str1 == NULL||str2 == NULL)
    {
        cout<<"No enough memory!"<<endl;
        return -1;
    }


    cout<<"Enter two strings:"<<endl;
    cin>>str1>>str2;

    int result = 0;
    result = strcmp(str1,str2);
    if(result>0)
        cout<<"""<<str1<<"""<<"is bigger than "<<"""<<str2<<"""<<endl;
    else if(result<0)
        cout<<"""<<str2<<"""<<"is bigger than "<<"""<<str1<<"""<<endl;
    else
        cout<<"They are equal"<<endl;
    

    delete [] str1;
    delete [] str2;