A) Stacks [Linked List]

gistfile1.cpp

//Stacks using linked list 
#include<iostream.h> 
  
struct node 
{ 
       char name[20]; 
       int age; 
       node *link; 
}; 
  
class stack 
{ 
      node *top; 
      public: stack() 
              { 
                     top=NULL; 
              } 
      void stackpush(); 
      void stackpop(); 
      void display(); 
}obj; 
  
void stack::stackpush() 
{ 
     node *temp; 
     temp=new node; 
     cout<<"\nEnter the Name: "; 
     cin>>temp->name; 
     cout<<"Enter the Age: "; 
     cin>>temp->age; 
     temp->link=NULL; 
     if(top==NULL) 
     { 
                  top=temp; 
                  } 
     else
     {  
         temp->link=top; 
         top=temp; 
         } 
} 
  
  
void stack::stackpop() 
{ 
     node *temp; 
     if(top==NULL) 
     { 
                  cout<<"Stack empty"; 
                  } 
     else
     { 
         temp=top; 
         top=top->link; 
         temp->link=NULL; 
         delete temp; 
     } 
} 
  
void stack::display() 
{ 
     node *temp; 
     temp=top; 
     int i=0; 
     while(temp!=NULL) 
     { 
                      i++; 
                      cout<<"\nRecord "<<i<<" (From top to bottom)"; 
                      cout<<"\nName: "<<temp->name; 
                      cout<<"\nAge: "<<temp->age<<"\n\n\n"; 
                      temp=temp->link; 
     } 
} 
  
int main() 
{ 
  int ch; 
  char opt='y'; 
  do
  { 
       cout<<"MAIN MENU"<<endl; 
       cout<<"1.Add an element"<<endl; 
       cout<<"2.Delete an element"<<endl; 
       cout<<"3.Display the stack"<<endl; 
       cout<<"4.Exit"<<endl; 
       cout<<"\nEnter your choice: "; 
       cin>>ch; 
         
       switch(ch) 
       { 
                 case 1: 
                      do
                      { 
                          obj.stackpush(); 
                          cout<<"Do you wanna enter data for more employees?(y/n): "; 
                          cin>>opt; 
                      }while(opt=='y'); 
                      break; 
                 case 2: 
                      opt='y'; 
                      do
                      { 
                          obj.stackpop(); 
                          cout<<"Do you wanna continue?(y/n): "; 
                          cin>>opt; 
                      }while(opt=='y'); 
                      break; 
                 case 3: 
                      obj.display(); 
                      break; 
                 case 4:exit(0); 
       } 
  }while(ch!=4); 
         
       system("pause"); 
       return 0;