# HackerRank Inserting a Node Into a Sorted Doubly Linked List solution

In this HackerRank Inserting a Node into a sorted doubly linked list Interview preparation kit problem You have Given a reference to the head of a doubly-linked list and an integer, data, create a new DoublyLinkedListNode object having data value data and insert it at the proper location to maintain the sort.

## Problem solution in Python programming.

```#!/bin/python3

import math
import os
import random
import re
import sys

def __init__(self, node_data):
self.data = node_data
self.next = None
self.prev = None

def __init__(self):
self.tail = None

def insert_node(self, node_data):

else:
self.tail.next = node
node.prev = self.tail

self.tail = node

while node:
fptr.write(str(node.data))

node = node.next

if node:
fptr.write(sep)

# Complete the sortedInsert function below.

#
#
#     int data
#
#
if cur.data>data or cur.data==data:
node.next=cur
cur.prev=node
while cur.next:
if (cur.data<data and cur.next.data>data) or cur.data==data:
node.next=cur.next
cur.next.prev=node
node.prev=cur
cur.next=node
cur=cur.next
if cur.data<data or cur.data==data:
node.prev=cur
cur.next=node

if __name__ == '__main__':
fptr = open(os.environ['OUTPUT_PATH'], 'w')

t = int(input())

for t_itr in range(t):
llist_count = int(input())

for _ in range(llist_count):
llist_item = int(input())
llist.insert_node(llist_item)

data = int(input())

fptr.write('\n')

fptr.close()```

## Problem solution in Java Programming.

```import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

public int data;

this.data = nodeData;
this.next = null;
this.prev = null;
}
}

this.tail = null;
}

public void insertNode(int nodeData) {

} else {
this.tail.next = node;
node.prev = this.tail;
}

this.tail = node;
}
}

public static void printDoublyLinkedList(DoublyLinkedListNode node, String sep, BufferedWriter bufferedWriter) throws IOException {
while (node != null) {
bufferedWriter.write(String.valueOf(node.data));

node = node.next;

if (node != null) {
bufferedWriter.write(sep);
}
}
}

// Complete the sortedInsert function below.

/*
*
*     int data;
* }
*
*/
return node;
} else if (data <= head.data) {
return node;
} else {
}
}

private static final Scanner scanner = new Scanner(System.in);

public static void main(String[] args) throws IOException {
BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

int t = scanner.nextInt();
scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

for (int tItr = 0; tItr < t; tItr++) {

int llistCount = scanner.nextInt();
scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

for (int i = 0; i < llistCount; i++) {
int llistItem = scanner.nextInt();
scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

llist.insertNode(llistItem);
}

int data = scanner.nextInt();
scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

bufferedWriter.newLine();
}

bufferedWriter.close();

scanner.close();
}
}
```

### Problem solution in C++ programming.

```#include <bits/stdc++.h>

using namespace std;

public:
int data;

this->data = node_data;
this->next = nullptr;
this->prev = nullptr;
}
};

public:

this->tail = nullptr;
}

void insert_node(int node_data) {

} else {
this->tail->next = node;
node->prev = this->tail;
}

this->tail = node;
}
};

while (node) {
fout << node->data;

node = node->next;

if (node) {
fout << sep;
}
}
}

while (node) {
node = node->next;

free(temp);
}
}

// Complete the sortedInsert function below.

/*
*
*     int data;
* };
*
*/

node->data = data;
node->next = node->prev = NULL;

return node;

return node;
}

}

int main()
{
ofstream fout(getenv("OUTPUT_PATH"));

int t;
cin >> t;
cin.ignore(numeric_limits<streamsize>::max(), '\n');

for (int t_itr = 0; t_itr < t; t_itr++) {

int llist_count;
cin >> llist_count;
cin.ignore(numeric_limits<streamsize>::max(), '\n');

for (int i = 0; i < llist_count; i++) {
int llist_item;
cin >> llist_item;
cin.ignore(numeric_limits<streamsize>::max(), '\n');

llist->insert_node(llist_item);
}

int data;
cin >> data;
cin.ignore(numeric_limits<streamsize>::max(), '\n');

fout << "\n";

}

fout.close();

return 0;
}```

### Problem solution in C programming.

```#include <assert.h>
#include <limits.h>
#include <math.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int data;
};

};

node->data = node_data;
node->next = NULL;
node->prev = NULL;

return node;
}

} else {
}

}

while (node) {
fprintf(fptr, "%d", node->data);

node = node->next;

if (node) {
fprintf(fptr, "%s", sep);
}
}
}

while (node) {
node = node->next;

free(temp);
}
}

// Complete the sortedInsert function below.

/*
*
*     int data;
* };
*
*/
if (head == NULL) return new;
return new;
}

while (curr->next != NULL && curr->next->data < new->data) {
curr = curr->next;
}

if (curr->next == NULL) { // Insert at end of list
curr->next = new;
new->prev = curr;
} else { // Insert somewhere in the middle
new->next = curr->next;
curr->next->prev = curr;
curr->next = new;
}

}

int main()
{
FILE* fptr = fopen(getenv("OUTPUT_PATH"), "w");

char* t_endptr;
int t = strtol(t_str, &t_endptr, 10);

if (t_endptr == t_str || *t_endptr != '\0') { exit(EXIT_FAILURE); }

for (int t_itr = 0; t_itr < t; t_itr++) {
llist->tail = NULL;

char* llist_count_endptr;
int llist_count = strtol(llist_count_str, &llist_count_endptr, 10);

if (llist_count_endptr == llist_count_str || *llist_count_endptr != '\0') { exit(EXIT_FAILURE); }

for (int i = 0; i < llist_count; i++) {
char* llist_item_endptr;
int llist_item = strtol(llist_item_str, &llist_item_endptr, 10);

if (llist_item_endptr == llist_item_str || *llist_item_endptr != '\0') { exit(EXIT_FAILURE); }

}

char* data_endptr;
int data = strtol(data_str, &data_endptr, 10);

if (data_endptr == data_str || *data_endptr != '\0') { exit(EXIT_FAILURE); }

char *sep = " ";

fprintf(fptr, "\n");

}

fclose(fptr);

return 0;
}

size_t alloc_length = 1024;
size_t data_length = 0;
char* data = malloc(alloc_length);

while (true) {
char* cursor = data + data_length;
char* line = fgets(cursor, alloc_length - data_length, stdin);

if (!line) { break; }

data_length += strlen(cursor);

if (data_length < alloc_length - 1 || data[data_length - 1] == '\n') { break; }

size_t new_length = alloc_length << 1;
data = realloc(data, new_length);

if (!data) { break; }

alloc_length = new_length;
}

if (data[data_length - 1] == '\n') {
data[data_length - 1] = '\0';
}

data = realloc(data, data_length);

return data;
}```

### Problem solution in JavaScript programming.

```'use strict';

const fs = require('fs');

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
inputString += inputStdin;
});

process.stdin.on('end', _ => {
inputString = inputString.replace(/\s*\$/, '')
.split('\n')
.map(str => str.replace(/\s*\$/, ''));

main();
});

return inputString[currentLine++];
}

constructor(nodeData) {
this.data = nodeData;
this.next = null;
this.prev = null;
}
};

constructor() {
this.tail = null;
}

insertNode(nodeData) {

} else {
this.tail.next = node;
node.prev = this.tail;
}

this.tail = node;
}
};

while (node != null) {
ws.write(String(node.data));

node = node.next;

if (node != null) {
ws.write(sep);
}
}
}

// Complete the sortedInsert function below.

/*
*
*     int data;
* }
*
*/
}
if(data < current.data) {
newNode.next = current;
current.prev = newNode;
return newNode;
}

while(current != null) {
if(data >= current.data) {
if(current.next == null) {
current.next = newNode;
newNode.prev = current;

}

if(current.next.data >= data) {
newNode.next = current.next;
newNode.prev = current;
current.next = newNode;
newNode.next.prev = newNode;

}
}

current = current.next;
}

}

function main() {
const ws = fs.createWriteStream(process.env.OUTPUT_PATH);

for (let tItr = 0; tItr < t; tItr++) {

for (let i = 0; i < llistCount; i++) {
llist.insertNode(llistItem);
}