iam having problem in displaying the elements present in singly linkllist.here is my code below plz check the whole code and pointout the errors and give their solution plzzzzz.
#include<iostream.h>
#include<conio.h>
#include<stdlib.h>
struct node
{
int data;
node *ptr;
};
node *first,*p,*nn;
class list
{
public:
void inslast(int);
void insbeg(int);
void ins_after(int,int);
void ins_bef(int,int);
void delelement(int);
void delbeg();
void dellast();
void disp();
void search(int);
list()
{first=NULL;}
};
void list::inslast(int x)
{
nn=new node;
nn->data=x;
p=first;
while(p->ptr!=NULL)
{ p=p->ptr;}
p->ptr=nn;
nn->ptr=NULL;
p=nn;
cout<<"\n\t\t Inserted successfully at the end..\n ";
disp();
}
void list:: insbeg(int x)
{
nn=new node;
nn->data=x;
nn->ptr=first;
first=nn;
//p=first;
cout<<"\n\t\t Inserted successfully at the begining..\n";
disp();
}
void list::delelement(int x)
{
node *q;
p=first;
while(p->data==x)
{
q=p;
p=p->ptr;
}
q->ptr=p->ptr;
cout<<"\n\t\t Successfully deleted..\n";
}
void list:: delbeg()
{
cout<<" \n\t\t The list before deletion: ";
disp();
p=first;
p=p->ptr;
first=p;
cout<<"\n\t\t Successfully deleted..\n";
}
void list:: dellast()
{
cout<<"\n\t\t The list before deletion: ";
disp();
node *q;
p=first;
while(p->ptr!=NULL)
{
q=p;
p=p->ptr;
}
q->ptr=NULL;
cout<<"\n\t\t Successfully deleted..\n";
}
void list::disp()
{
p=first;
while(p->ptr!=NULL)
{
cout<<" "<<p->data;
p=p->ptr;
}
}
void list::ins_after(int value,int pos)
{
nn=new node;
nn->data=value;
p=first;
while(p->data!=pos)
{ p=p->ptr; }
nn->ptr=p->ptr;
p->ptr=nn;
cout<<" \n\t\t Inserted successfully at the position.."<<pos;
disp();
}
void list::ins_bef(int value,int pos)
{
node *q;
nn=new node;
nn->data=value;
p=first;
while(p->data!=NULL)
{
q=p;
p=p->ptr;
}
nn->ptr=p;
q->ptr=nn;
cout<<"\n\t\t Inserted successfully at the position.."<<pos;
disp();
}
void list::search(int value)
{
p=first;
while(p->ptr!=NULL)
{
if(p->data==value)
{
cout<<"\n\t\tYes the element "<<value<<" is found";
}
p=p->ptr;
}
cout<<"\n\t\t Element "<<value<<" not found";
void main()
{
list l;
int ch,val,req,sel;
do
{
clrscr();
cout<<"\t\t..:::****~WELCOME~..:::****\n";
cout<<" \n\n\t\tFucntions in this single Link list..\n";
cout<<"\t\t 1.Insertion 2.Deletion 3.Display 4.Search 5.Exit";
cout<<" \n\t\t Enter choice for fucntion: ";
cin>>ch;
switch(ch)
{
case 1:
cout<<"\n\t\t 1.Insertion at begining:";
cout<<" \n\t\t 2.Insertion at the end: ";
cout<<"\n\t\t 3.Insertion after required node:";
cout<<"\n\t\t 4.Insertion before required node:";
cout<<" \n\t\t Enter ur choice:";
cin>>sel;
cout<<" \n\t\tEnter the value to insert in linklist:";
cin>>val;
switch(sel)
{
case 1:
l.insbeg(val);
break;
case 2:
l.inslast(val);
break;
case 3:
cout<<" \n\t\tEnter the value after which the node to be inserted:";
cin>>req;
l.ins_after(val,req);
break;
case 4:
cout<<" \n\t\t Enter the value before which the node to be inserted:";
cin>>req;
l.ins_bef(val,req);
default:
cout<<"\n\t\t Invalid choice: ";
}
break;
case 2:
cout<<" \n\t\t 1.Delete the first element.";
cout<<" \n\t\t 2.Delete the last element.";
cout<<" \n\t\t 3.Enter the element to delete from the list";
cout<<" Enter ur choice:";
cin>>sel;
switch(sel)
{
case 1:
l.delbeg();
cout<<" \n\t\tThe list after deletion: ";
l.disp();
break;
case 2:
l.dellast();
cout<<"\n\t\t The list after deletion:";
l.disp();
break;
case 3:
l.disp();
cout<<"\n\t\t Enter the element to delete : ";
cin>>val;
l.delelement(val);
cout<<"\n\t\t The list after deletion:";
l.disp();
break;
default:
cout<<" \n\t\tThe option is invalid...";
break;
}
break;
case 3:
l.disp();
break;
case 4:
l.disp();
cout<<"\n\t\t Enter the element to search:";
cin>>val;
l.search(val);
break;
case 5:
exit(1);
default:
cout<<" \n\t\t The option selected is invalid... ";
}
}
while(1);
getch();
}
