Top most value of the stack

//stack program
template<class T>
class stack
{
 private:
  T *s;
  int top,size;
 public:
    stack(int k=40);
      int isempty();
    T topmost();
 };
 template<class T>
stack<T>::stack(int k)
{
 top=-1;
 size=k;
 s=new T[size];
}
//isempty()
template<class T>
int stack<T>::isempty()
{
 return(top==-1);
}
//isfully

template<class T>
T stack<T>::topmost()
{
 if(isempty())
  return(-1);
 else
  return(s[top]);
}void main()
{
 int ch,k,x;
  cout<<"enter size of the stack\n";
  cin>>k;
        stack<int> a(k);
        x=a.topmost();
        if( x==-1)
          cout<<"stack is empty\n";
       else
         cout<<"top most value of the stack is="<<x<<endl;
  getch();
}
  
      

Basic stack operation: