write a c++ a menu driven program using class to perform all arithmetic operation +,-*,/ using inline function

/*write a c++ a menu driven program using class to perform all arithmetic
operation +,-*,/ using inline function*/
#include<conio.h>
#include<stdlib.h>
#include<iostream.h>
#include<float.h>
class arith
{
public:inline void add(int a,int b)
       {
       int c;
       c=a+b;
       cout<<"\nthe addition is:-"<<c;
       }
       inline void sub(int a,int b)
       {
       int c;
       c=a-b;
       cout<<"\nthe substraction is:-"<<c;
       }
       inline void mult(int a,int b)
       {
       int c;
       c=a*b;
       cout<<"\nthe multiplication is:-"<<c;
       }
       inline void div(int a,int b)
       {
       float c;
       c=a/(b+0.0);
       cout<<"\nthe division is:-"<<c;
       }
};
int main()
{
arith a;
int ch,n1,n2;
clrscr();
while(1)
{
cout<<"\n1:addition";
cout<<"\n2:substraction";
cout<<"\n3:multiplication";
cout<<"\n4:division";
cout<<"\n5:exit";
cout<<"\nenter your choice:-";
cin>>ch;
switch(ch)
{
case 1:cout<<"\nenter two number";
       cin>>n1>>n2;
       a.add(n1,n2);
       break;
case 2:cout<<"\nenter two number";
       cin>>n1>>n2;
       a.sub(n1,n2);
       break;
case 3:cout<<"\nenter two number";
       cin>>n1>>n2;
       a.mult(n1,n2);
       break;
case 4:cout<<"\nenter two number";
       cin>>n1>>n2;
       a.div(n1,n2);
       break;
case 5:exit(0);
default:cout<<"\nyou entered wrong choice";
}
}
getch();
return 0;
}
/*enter your choice:-1
                                                                               
enter two number3 4                                                            
                                                                               
the addition is:-7                                                             
1:addition                                                                     
2:substraction                                                                 
3:multiplication                                                               
4:division                                                                     
5:exit                                                                         
enter your choice:-2                                                           
                                                                               
enter two number3 2                                                            
                                                                               
the substraction is:-1                                                         
1:addition                                                                     
2:substraction                                                                 
3:multiplication                                                               
4:division
5:exit                                                                         
enter your choice:-3                                                           
                                                                               
enter two number4 5                                                            
                                                                               
the multiplication is:-20                                                      
1:addition                                                                     
2:substraction                                                                 
3:multiplication                                                               
4:division                                                                     
5:exit                                                                         
enter your choice:-4

enter two number4 6

the division is:-0.666667
1:addition
2:substraction
3:multiplication
4:division
5:exit
enter your choice:-6

you entered wrong choice
1:addition
2:substraction
3:multiplication
4:division
5:exit
enter your choice:-5
*/