Data Structures - Queue Implementation using Linked List

       #include < iostream.h >
  #include < conio.h >
  #include < stdlib.h >
  struct node
   {
     char name[20];
     int age;
     float height;
     node *nxt;
   };
  node *start_ptr=NULL;
  int main()
  {
     void push ();
     void pop();
     char ch;
     clrscr();
     cout<<"Queue";
     cout<<"-----";
     do
     {
       cout<<"Select an operation";
       cout<<"u->push";
       cout<<"o->pop";
       cout<<"e->exit";
       cin>>ch;
       switch(ch)
       {
         case 'u':
           push();
           break;
         case 'o':
           pop();
           break;
         case 'e':
           exit(0);
       }
     }while(ch!='e');
     return 0;
  }
  void pop()
  {
     node *temp1,*temp2;
     if(start_ptr==NULL)
       cout<<"The list is empty";
     else
     {
       temp1=start_ptr;
       temp2=temp1;
       while(temp1->nxt!=NULL)
       {
         temp2=temp1;
         temp1=temp1->nxt;
       }
       if(temp1==temp2)
       {
         cout<< temp1->name<<",";
         cout<< temp1->age<<", ";
         cout<< temp1->height;
         start_ptr=NULL;
       }
       else
       {
         cout<< temp1->name<<", ";
         cout<< temp1->age<<", ";
         cout<< temp1->height;
         temp2->nxt=NULL;
         delete temp1;
       }
     }
  }
  void push ()
   {
     node *temp;
     temp = new node;
     cout << "Please enter the name of the person: ";
     cin >> temp->name;
     cout << "Please enter the age of the person: ";
     cin >> temp->age;
     cout << "Please enter the height of the person: ";
     cin >> temp->height;
     if (start_ptr == NULL)
     {
       temp->nxt=NULL;
       start_ptr = temp;
     }
     else
     {
       temp->nxt=start_ptr;
       start_ptr=temp;
     }
   }