C++: Classes And Objects

Multiple classes

If required we can have multiple classes in a single program. The classes may or may not be related.

Question:1
C++ program to declare a class named student with attributes as roll and name. Declare another class named physical with attributes as age, height and weight. Take input for the details and display them.
Sol:

#include <iostream>
#include<conio.h>
using namespace std;
class student
{
private:
    int roll;
    char name[20];
public:
    void read();
    void show();
};
class physical
{
private:
    float age,ht,wt;
public:
    void read();
    void show();
};
void student::read()
{
    cout<<"Enter roll and name ";
    cin>>roll>>name;
}
void student::show()
{
    cout<<"roll "<<roll<<" name "<<name<<endl;
}
void physical::read()
{
    cout<<"Enter age, height and weight ";
    cin>>age>>ht>>wt;
}
void physical::show()
{
    cout<<"age "<<age<<" height "<<ht<<" weight "<<wt<<endl;
}
int main()
{
    student s;
    physical p;
    s.read(); p.read();
    s.show(); p.show();
    return(0);
}
/* Output */

Enter roll and name 101
Amit
Enter age, height and weight 10
5
3
roll 101 name Amit
age 10 height 5 weight 3

Question:2
C++ program to declare a class named employee with attributes as empno and name. Declare another class named office with attributes as deptno, deptname and salary. Take input for the details and display them.
Sol:

#include<iostream>
#include<conio.h>
using namespace std;
class employee
{
	private:
		int empno;
		char name[20];
	public:
		void read();
		void show();
};
class office
{
	private:
		int dno;
		char dname[20];
		float sal;
	public:
		void read();
		void show();
};
void employee::read()
{
	cout<<"Enter empno and name ";
	cin>>empno>>name;
}
void employee::show()
{
	cout<<"Empno "<<empno<<" Name "<<name<<endl;
}
void office::read()
{
	cout<<"Enter dno, dname and salary ";
	cin>>dno>>dname>>sal;
}
void office::show()
{
	cout<<"Dno "<<dno<<" Dname "<<dname<<" Salary "<<sal<<endl;
}
int main()
{
	employee e;
	office o;
	e.read(); o.read();
	e.show(); o.show();
	return(0);
}
/* Output */

Enter empno and name 1001
Amit
Enter dno, dname and salary 10
Sales
45000
Empno 1001 Name Amit
Dno 10 Dname Sales Salary 45000

Question:3
C++ program to declare a class named student with attributes as roll and name. Declare another class named marks with attributes as m1,m2,m3,total and per. Take input for the details and display them.
Sol:

#include <iostream>
#include<conio.h>
using namespace std;
class student
{
private:
    int roll;
    char name[20];
public:
    void read();
    void show();
};
class marks
{
private:
    float m1,m2,m3,total,per;
public:
    void read();
    void cal();
    void show();
};
void student::read()
{
    cout<<"Enter roll and name ";
    cin>>roll>>name;
}
void student::show()
{
    cout<<"roll "<<roll<<" name "<<name<<endl;
}
void marks::read()
{
    cout<<"Enter m1,m2 and m3 ";
    cin>>m1>>m2>>m3;
}
void marks::cal()
{
    total=m1+m2+m3;
    per=total/3;
}
void marks::show()
{
    cal();
    cout<<"m1 "<<m1<<" m2 "<<m2<<" m3 "<<m3<<endl;
    cout<<"Total "<<total<<" Per "<<per<<endl;
}
int main()
{
    student s;
    marks m;
    s.read(); m.read();
    s.show(); m.show();
    return(0);
}
/* Output */

Enter roll and name 1002
Sumit
Enter m1,m2 and m3 95
96
93
roll 1002 name Sumit
m1 95 m2 96 m3 93
Total 284 Per 94.6667