Adding cpp code for double linked list

Linked List/Double Linked List.cpp

@@ -0,0 +1,157 @@
+/*
+All Basics Features of Double Linked List
+@author: nmanish_0128
+
+- creating a Double Linked list Node
+- printing a Double linked list
+- inserting in a element
+- deleting a element
+- searching a element
+*/
+
+#include <iostream>
+using namespace std;
+
+// class for Node
+class node {
+    public:
+    int data;
+    node* prev;
+    node* next;
+    node(){
+        next=NULL;
+        prev=NULL;
+    }
+};
+
+// printing an Linked List
+void print(node* head){
+    node* ptr = head;
+    if(head==NULL){
+        cout<<"Linked List is empty"<<endl;
+    }else{
+        do{
+            cout<<ptr->data<<" ";
+            ptr=ptr->next;
+        }while(ptr!=NULL);
+    }
+}
+
+// inserting an element in a Linked List
+
+//insert at head
+void insertHead(node* &head,int val){
+    node* new_node = new node();
+    new_node->data = val;
+    if(head==NULL){
+        head=new_node;
+        new_node->next=NULL;
+    }else{
+        head->prev= new_node;
+        new_node->next = head;
+        head=new_node;
+    }
+}
+
+//insert at tail
+void insertTail(node* head,int val){
+    node* ptr = head;
+    node* new_node = new node();
+    new_node->data=val;
+    while(ptr->next!=NULL){
+        ptr=ptr->next;
+    }
+    new_node->prev=ptr;
+    ptr->next=new_node;
+}
+
+// insert before a given val
+void insertBefore(node* head,int key,int val){
+    node* ptr = head;
+    while(ptr->next->data!=key){
+        if(ptr->next->next==NULL){
+            cout<<"key not found - insertBefore key("<<key<<")"<<endl;
+            return;                
+        }
+        ptr=ptr->next;
+    }
+    node* new_node= new node();
+    new_node->data=val;
+    ptr->next->prev=new_node;
+    new_node->next=ptr->next;
+    new_node->prev=ptr;
+    ptr->next = new_node;
+}
+
+//insert after a given val
+void insertAfter(node* head,int key,int val){
+    node* ptr = head;
+    while(ptr->data!=key){
+        if(ptr->next==NULL){
+            cout<<"key not found - insertAfter key("<<key<<")"<<endl;
+            return;
+        }
+        ptr=ptr->next;
+    }
+    node* new_node= new node();
+    new_node->data=val;
+    ptr->next->prev=new_node;
+    new_node->next=ptr->next;
+    new_node->prev=ptr;
+    ptr->next = new_node;
+}
+
+//delete a given element
+void Delete(node* &head,int key){
+    node* ptr = head;
+    if(ptr->data==key){
+        node* temp=ptr;
+        head=ptr->next;
+        head->prev=NULL;
+        free(temp);
+        return;
+    }
+    while(ptr->next->data!=key){
+        if(ptr->next->next==NULL){
+            cout<<"key not found - Delete key("<<key<<")"<<endl;
+            return;
+        }
+        ptr=ptr->next;
+    }
+    node* temp=ptr->next;
+    temp->next->prev=ptr;
+    ptr->next = temp->next;
+    free(temp);
+}
+
+//search a element in a Linked List
+void Search(node* head,int key){
+    node* ptr = head;
+    while(ptr->data!=key){
+        if(ptr->next==NULL){
+            cout<<"key not found - search key("<<key<<")"<<endl;
+            return;
+        }
+        ptr=ptr->next;
+    }
+    cout<<"key found"<<endl;
+}
+
+int main(){
+    node* head=NULL;
+    insertHead(head,3);
+    insertHead(head,9);
+    insertTail(head,8);
+    insertTail(head,4);
+    insertBefore(head,8,1);
+    insertAfter(head,8,0);
+    Delete(head,8);
+    Search(head,0);
+    print(head);
+    return 0;
+}
+
+/*
+All Basics Features of Double Linked List
+@author: nmanish_0128
+*/