# Insert value in sorted way in a sorted doubly linked list

Given a sorted doubly linked list and a value to insert, write a function to insert the value in sorted way.

Doubly Linked List after insertion of 9

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Algorithm:
Let input doubly linked list is sorted in increasing order.
New node passed to the function contains data in the data part and previous and next link are set to NULL.

```sortedInsert(head_ref, newNode)

newNode->next->prev = newNode

else
while (current->next != NULL and
current->next->data data)
current = current->next

newNode->next = current->next
if current->next != NULL
newNode->next->prev = newNode

current->next = newNode
newNode->prev = current
```
```// C++ implementation to insert value in sorted way
// in a sorted doubly linked list
#include <bits/stdc++.h>

using namespace std;

// Node of a doubly linked list
struct Node {
int data;
struct Node* prev, *next;
};

// function to create and return a new node
// of a doubly linked list
struct Node* getNode(int data)
{
// allocate node
struct Node* newNode =
(struct Node*)malloc(sizeof(struct Node));

// put in the data
newNode->data = data;
newNode->prev = newNode->next = NULL;
return newNode;
}

// function to insert a new node in sorted way in
// a sorted doubly linked list
void sortedInsert(struct Node** head_ref, struct Node* newNode)
{
struct Node* current;

// if list is empty

// if the node is to be inserted at the beginning
// of the doubly linked list
else if ((*head_ref)->data >= newNode->data) {
newNode->next->prev = newNode;
}

else {

// locate the node after which the new node
// is to be inserted
while (current->next != NULL &&
current->next->data < newNode->data)
current = current->next;

/* Make the appropriate links */
newNode->next = current->next;

// if the new node is not inserted
// at the end of the list
if (current->next != NULL)
newNode->next->prev = newNode;

current->next = newNode;
newNode->prev = current;
}
}

// function to print the doubly linked list
{
cout << head->data << " ";
}
}

// Driver program to test above
int main()
{

// insert the following nodes in sorted way
struct Node* new_node = getNode(8);
new_node = getNode(5);
new_node = getNode(3);
new_node = getNode(10);
new_node = getNode(12);
new_node = getNode(9);

cout << "Created Doubly Linked Listn";
return 0;
}
```

Output:

```Created Doubly Linked List
3 5 8 9 10 12
```

Time Complexity: O(n)

This article is contributed by Ayush Jauhari. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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