Cube and Power without built-in functions Cpp / C++

This Cpp program is for using the Math functions without the Math.h class. 


The below program performs the operations of finding cube and power of a number without the built-in math functions. The Functions for the same are created by the programmer.

#include<iostream.h>
#include<conio.h>
#include<process.h>

class Math_1
{
 int cu,num,base,pow,res;
 public :
 Math_1(){}
 Math_1(int n)
 {
  num=n;
 }
 Math_1(int b,int p)
 {
  base=b;
  pow=p;
 }
 ~Math_1(){}
 void cube();
 void power();
};

void Math_1 :: cube()
{
 cu=num*num*num;
 cout<<endl;
 cout<<"Cube of "<<num<<" : "<<cu;
}

void Math_1 :: power()
{

 for(int i=0;i<pow;i++)
  res=res*base;
 cout<<endl;
 cout<<"Result : "<<res;
}

void main()
{
 int num,b,p,ch;
 clrscr();
 cout<<"1. Cube"<<endl;
 cout<<"2. Power"<<endl<<endl;
 cout<<"3. End";
 while(1)
 {
 cout<<"\n\nEnter your choice : ";
 cin>>ch;
 switch(ch)
 {
 case 1:
  cout<<"Enter Number : ";
  cin>>num;
  Math_1 m1(num);
  m1.cube();
  break;

 case 2:
  cout<<"Enter Base : ";
  cin>>b;
  cout<<"Enter Power : ";
  cin>>p;
  Math_1 m2(b,p);
  m2.power();
  break;

 default :
  cout<<"Please Enter Right Choice.";
  exit(0);

 }
 }
 getch();
}