LinkedList.cpp

#include <iostream>
using namespace std;
class Node
{
public:
int data;
Node *next;
};
class LinkedList
{
private:
Node *first;
public:
LinkedList(){first=NULL;}
LinkedList(int A[],int n);
~LinkedList();
void Display();
void Insert(int index,int x);
int Delete(int index);
int Length();
};
LinkedList::LinkedList(int A[],int n)
{
Node *last,*t;
int i=0;
first=new Node;
first->data=A[0];
first->next=NULL;
last=first;
for(i=1;i<n;i++)
{
t=new Node;
t->data=A[i];
t->next=NULL;
last->next=t;
last=t;
}
}
LinkedList::~LinkedList()
{
Node *p=first;
while(first)
{
first=first->next;
delete p;
p=first;
}
}
void LinkedList::Display()
{
Node *p=first;
while(p)
{
cout<<p->data<<" ";
p=p->next;
}
cout<<endl;
}
int LinkedList::Length()
{
Node *p=first;
int len=0;
while(p)
{
len++;
p=p->next;
}
return len;
}
void LinkedList::Insert(int index,int x)
{
Node *t,*p=first;
if(index <0 || index > Length())
return;
t=new Node;
t->data=x;
t->next=NULL;
if(index==0)
{
t->next=first;
first=t;
}
else
{
for(int i=0;i<index-1;i++)
p=p->next;
t->next=p->next;
p->next=t;
}
}
int LinkedList::Delete(int index)
{
Node *p,*q=NULL;
int x=-1;
if(index < 1 || index > Length())
return -1;
if(index==1)
{
p=first;
first=first->next;
x=p->data;
delete p;
}
else
{
p=first;
for(int i=0;i<index-1;i++)
{
q=p;
p=p->next;
}
q->next=p->next;
x=p->data;
delete p;
}
return x;
}
int main()
{
int A[]={1,2,3,4,5};
LinkedList l(A,5);
l.Insert(3,10);
l.Display();
return 0;
}