第八章作业

傷城~ 2022-08-01 11:27 219阅读 0赞

第八章  作业

1.\#include <iostream>  
\#include <cmath>  
using namespace std;  
double s(double,double,double);  
void main()  
\{  
 double a,b,c,d,x1,x2;  
 cout<<"输入a,b,c:";  
 cin>>a>>b>>c;  
 d=-b/(2\*a);  
 x1=d+s(a,b,c);  
 x2=d-s(a,b,c);  
 cout<<"x1="<<x1<<endl;  
 cout<<"x2="<<x2<<endl;  
\}  
double s(double a,double b,double c)  
\{  
 double k;  
 k=b\*b-4\*a\*c;  
 if(k<0)  
cout<<"此方程无实数根！"<<endl;  
 else  
return sqrt(k)/(2\*a);  
\}

![Center][]

2. \#include <iostream>  
\#include <string>  
using namespace std;  
class Student  
\{  
public:  
Student(int n,string nam)  
\{  
num=n;  
name=nam;  
  
\}  
~Student()  
\{  
cout<<"destructor"<<endl;  
\}  
void show\_data();  
private:  
int num;  
string name;  
\};  
void Student::show\_data()  
\{  
 cout<<"num:"<<num<<endl;  
 cout<<"name:"<<name<<endl;  
\}  
void fun()  
\{  
 Student s1(3907,"xiongxian");  
 s1.show\_data();  
\}  
int main()  
\{  
cout<<"main begin"<<endl;  
cout<<"call fun()"<<endl;  
fun();  
cout<<"main end"<<endl;  
return 0;  
\}

3. \#include <iostream>  
\#include <string>  
using namespace std;  
class Student  
\{  
public:  
Student(int n,string nam,int a,string addr,char s,float sco)  
\{num=n;name=nam;age=a;address=addr;sex=s;score=sco;\}  
void show\_data();  
private:  
int num;  
string name;  
int age;  
string address;  
char sex;  
float score;  
\};  
void Student::show\_data()  
\{  
 cout<<"num:"<<num<<endl;  
 cout<<"name:"<<name<<endl;  
 cout<<"age:"<<age<<endl;  
 cout<<"address:"<<address<<endl;  
 cout<<"sex:"<<sex<<endl;  
 cout<<"score:"<<score<<endl;  
\}  
int main()  
\{  
 Student s1(1,"yenianfeng",20,"jiangxi",'M',100);  
 s1.show\_data();  
\}

![Center 1][]

[Center]: /images/20220731/9a4cc448ebf14fed824383a8931651a5.png
[Center 1]: /images/20220731/8c4ab632929646bfaf807ca05b21e5a7.png