#include<iostream> #include<string> using namespace std; class shape { public: double width; double length; shape(double width=0,double length=0) :width(width), length(length){} }; class Rectangle :public shape { public: double get_Aera() { return (width * length); } }; struct Student { string name; int age; double score; Student(string name="",int age=0,double score=0):name(name),age(age),score(score){} }; int main() { Rectangle r(3.4,4.5); cout << r.get_Aera() << endl; Student s("Tom", 20, 90); cout << s.name << s.age << s.score << endl; return 0; }改正它

代码中有两个问题需要修正：

1. 头文件和命名空间应该写在 #include 和 main 函数之间；
2. 打印学生信息时应该分别输出各个属性，并在输出字符串之间加上空格。

修改后的代码如下：

#include<iostream>
#include<string>

using namespace std;

class shape {
public:
    double width;
    double length;
    shape(double width=0, double length=0) :width(width), length(length) {}
};

class Rectangle :public shape {
public:
    double get_Aera() {
        return (width * length);
    }
};

struct Student {
    string  name;
    int age;
    double score;
    Student(string name="", int age=0, double score=0):name(name), age(age), score(score) {}
};

int main() {
    Rectangle r(3.4, 4.5);
    cout << r.get_Aera() << endl;
    Student s("Tom", 20, 90);
    cout << s.name << " " << s.age << " " << s.score << endl;
    return 0;
}