软工C++复习题答案

1. #include <iostream>
using namespace std;
long int sum(int n)
{ int s=0;
if ( n==1) s=1;
else if(n>1) s=sum(n-1)+n*n;
return s; }
void main( )
{ int n,sum1;
cin>>n;
sum1=sum(n);
cout<<"sum="<<sum1<<endl; }
2.#include<iostream>
using namespace std;
class Date
{
public:
Date () { year=1900;month=1;day=1; }
Date(int y,int m,int d):year(y),month(m),day(d){}
Date(const Date& b) { year=b.year; month=b.month; day=b.day; } void dispd() { cout<<year<<'-'<<month<<'-'<<day<<endl; } private:
int year,month, day;
};
class people
{ char name[11],number[7],sex[3],id[16];
Date birth;
public:
char* getName() { return name; }
char* getNumber() { return number; }
char* getSex() { return sex; }
Date getBirth() { return birth; }
char* getId() { return id; }
people(){}
people(char* nm,char* no,char* gd,Date b,char* i):birth(b){ strcpy(name,nm);
strcpy(number,no);
strcpy(sex,gd);
strcpy(id,i);
}
people(people &p):birth(p.birth){
strcpy(name,);
strcpy(number,p.number);
strcpy(sex,p.sex);
strcpy(id,p.id);
}
};
class student:public people
{ char classNO[11];
public:
char* getcno() { return classNO; }
student() { }
student(char* nm,char* no,char* gd,Date b,char* i,char* clo):people(nm,no,gd,b,i) { strcpy(classNO,clo); }
student(student &s):people(s) { strcpy(classNO, s.classNO); } };
void main()
{ char name[20],num[10],sex[8],id[20],cno[10];
int y,m,d;
cin>>y>>m>>d;
Date dat(y,m,d),da;
cin>>name>>num>>sex>>id>>cno;
student ta(name,num,sex,dat,id,cno);
cout<<"ta的姓名:"<<ta.getName()<<endl;
cout<<"编号:"<<ta.getNumber()<<endl;
cout<<"性别:"<<ta.getSex()<<endl;
cout<<"身份证号:"<<ta.getId()<<endl;
da=ta.getBirth();
cout<<"出生日期:";
da.dispd();
cout<<"班号:"<<ta.getcno()<<endl;
student he(ta);
cout<<"****************************"<<endl;
cout<<"he的姓名:"<<he.getName()<<endl;
cout<<"编号:"<<he.getNumber()<<endl;
cout<<"性别:"<<he.getSex()<<endl;
da=he.getBirth();
cout<<"出生日期:";
da.dispd();
cout<<"班号:"<<he.getcno()<<endl; }
3.#include<iostream>
using namespace std;
class Point
{
public:
Point(double i, double j)
{ x=i; y=j; }
virtual double Area()=0;
virtual double Perim()=0;
private:
double x,y;
};
class Rectangle:public Point
{
public:
Rectangle(double i,double j,double k,double l);
double Area()
{ return w*h; }
double Perim()
{ return (w+h)*2; }
private:
double w,h;
};
Rectangle::Rectangle(double i,double j,double k,double l):Point(i,j) { w=k; h=l; }
class square:public Rectangle
{
public:
square(double i,double j,double s): Rectangle(),side(){}
double Area()
{ return side*side; }
double Perim()
{ return 4*side; }
private:
double side;
};
void fun(Point *s)
{ cout<<"面积=:"<<s->Area()<<','<<"周长="<<s->Perim()<<endl; } void main()
{
Rectangle rec(3.0,5.2,15.0,25.0);
cout<<"矩形的:";
fun(&rec);
square sq(5.0,8.0,12.0), *ps=&sq;
cout<<"正方形的:";
fun(ps);
}。