#include using namespace std; struct node { int data; node *link; }*n,*h,*p1,*s,*p; class sll { public: int key,count; sll() { n=new node; n->data=0; n->link=NULL; h=n; } void list() { cout<<"\n Enter the element : "; n=new node; cin>>n->data; n->link=h->link; h->link=n; } void insertmid() { s=h->link; cout<<"'\n Enter the key : "; cin>>key; cout<<"'\n Enter the element : "; while(s->link!=NULL&&s->data!=key) { s=s->link; } if(s->data==key) { n=new node; cin>>n->data; n->link=s->link; s->link=n; } } void deletemid() { s=h; if(s->link==NULL) { cout<<"\nList id empty"; } else { cout<<"\n Enter the key : "; cin>>key; while(s->link!=NULL) { if(s->data!=key) { p1=s; s=s->link; } else { p->link=s->link; delete s; } } } } void display() { count=0; p=h->link; while(p!=NULL) { cout<<"p->data"; count++; p=p->link;} cout<<"\n Number of nodes in a list : "<>z; switch(z) { case 1: s.list(); break; case 2: s.insertmid(); cout<<"value inserted"; break; case 3: s.insertmid(); cout<<"value deleted"; break; case 4: s.display(); cout<<"value displayed"; break; } }while(z=4); }

sll for middle