Here comes the first program /*stack adt using array*/

//implementing stack adt using array
#include<iostream.h>
#include<conio.h>
template <class t>
class stack{int top;t *a;
public: stack() {top=0;}
 void push(t &el) { a[++top]=el;  }
 t pop()
{
  if (top==0)
 {cout<<"stack empty";}
  return(a[top--]);
 }
 void display()
 { 
 if (top==0)
   { cout<<"stack is empty";    return;
   }  
 cout<<"the elements are \n"; 
 for(int i=top;i>0;i--)
 {cout<<a[i]<<" ";}
 }
  };
 void main()
   {
  stack <int> st;
  char cnt='y';
  int choice, element; 
  clrscr();  
 do
  {
  cout<<"main menu\n";   cout<<"1.push\n2.pop\n3.display\nenter your choice\n"; 
  cin>>choice;
  switch(choice) 
  { 
  case 1:cout<<"enter new element\n";
             cin>>element;
             st.push(element);
             break;  
  case 2:cout<<"deleted elements\n";
             st.pop();
             break;
  case 3:cout<<"the elements of stack are\n";  
             st.display();
             break;
  }
  cout<<" do u want to continue(y/n)";  
  cin>>cnt;   getch();
  } 
  while(cnt!='n'); 
  getch();
}

/* note:this is more simpler than the previous one ...If any one found bugs or logical errors please comment......*/