Algorithm
Problem Name: 30 days of code -
Objective
Today we will work with a Linked List. Check out the Tutorial tab for learning materials and an instructional video.
A Node class is provided for you in the editor. A Node object has an integer data field, data , and a Node instance pointer, next, pointing to another node (i.e.: the next node in the list). A Node insert function is also declared in your editor. It has two parameters: a pointer, head, pointing to the first node of a linked list, and an integer, data, that must be added to the end of the list as a new Node object.
Task
Complete the insert function in your editor so that it creates a new Node (pass data as the Node constructor argument) and inserts it at the tail of the linked list referenced by the head parameter. Once the new node is added, return the reference to the head node.
Note: The head argument is null for an empty list.
Input Format
The first line contains T, the number of elements to insert.
Each of the next T lines contains an integer to insert at the end of the list.
Output Format
Return a reference to the head node of the linked list.
Sample Input
STDIN Function
----- --------
4 T = 4
2 first data = 2
3
4
1 fourth data = 1
Sample Output
2 3 4 1
Code Examples
#1 Code Example with C Programming
Code -
C Programming
#include <stdlib.h>
#include <stdio.h>
typedef struct Node
{
int data;
struct Node* next;
}Node;
Node* insert(Node *head,int data)
{
Node * nod=
nod=(Node *)malloc(sizeof(Node));
nod->data=data;
if(head==NULL) {head =nod; return head;}
Node *p;
p=head;
while(p->next!=NULL)
p=p->next;
p->next=nod;
return head;
}
void display(Node *head)
{
Node *start=head;
while(start)
{
printf("%d ",start->data);
start=start->next;
}
}
int main()
{
int T,data;
scanf("%d",&T);
Node *head=NULL;
while(T-->0){
scanf("%d",&data);
head=insert(head,data);
}
display(head);
}
#2 Code Example with C++ Programming
Code -
C++ Programming
#include <iostream>
using namespace std;
class Node {
public:
int data;
Node *next;
Node(int d) {
data = d;
next = NULL;
}
};
class Solution {
public:
Node *insert(Node *head, int data) {
//Complete this method
if (head == NULL) head = new Node(data);
else {
Node *curr = head;
while (curr->next) curr = curr->next;
curr->next = new Node(data);
}
return head;
}
void display(Node *head) {
Node *start = head;
while (start) {
cout << start->data << " ";
start = start->next;
}
}
};
int main() {
Node *head = NULL;
Solution mylist;
int T, data;
cin >> T;
while (T-- > 0) {
cin >> data;
head = mylist.insert(head, data);
}
mylist.display(head);
}
#3 Code Example with C# Programming
Code -
C# Programming
using System;
class Node
{
public int data;
public Node next;
public Node(int d){
data=d;
next=null;
}
}
class Solution {
public static Node insert(Node head, int data)
{
if (head == null) head = new Node(data);
else {
Node curr = head;
while (curr.next != null) curr = curr.next;
curr.next = new Node(data);
}
return head;
}
public static void display(Node head)
{
Node start=head;
while(start!=null)
{
Console.Write(start.data+" ");
start=start.next;
}
}
static void Main(String[] args) {
Node head=null;
int T=Int32.Parse(Console.ReadLine());
while(T-->0){
int data=Int32.Parse(Console.ReadLine());
head=insert(head,data);
}
display(head);
}
}
#4 Code Example with Java Programming
Code -
Java Programming
import java.util.Scanner;
class Node {
int data;
Node next;
Node(int d) {
data = d;
next = null;
}
}
class Solution {
public static Node insert(Node head, int data) {
if (head == null) head = new Node(data);
else {
Node curr = head;
while (curr.next != null) curr = curr.next;
curr.next = new Node(data);
}
return head;
}
public static void display(Node head) {
Node start = head;
while (start != null) {
System.out.print(start.data + " ");
start = start.next;
}
}
public static void main(String args[]) {
Scanner sc = new Scanner(System.in);
Node head = null;
int N = sc.nextInt();
while (N-- > 0) {
int ele = sc.nextInt();
head = insert(head, ele);
}
display(head);
sc.close();
}
}
#5 Code Example with Javascript Programming
Code -
Javascript Programming
process.stdin.resume();
process.stdin.setEncoding('ascii');
var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;
process.stdin.on('data', function (data) {
input_stdin += data;
});
process.stdin.on('end', function () {
input_stdin_array = input_stdin.split("\n");
main();
});
function readLine() {
return input_stdin_array[input_currentline++];
}
function Node(data){
this.data=data;
this.next=null;
}
function Solution(){
this.insert = (head, data) => {
let node = new Node(data);
let current = head;
if (!head) {
// No list, this is the first node
return node;
} else {
// Traverse the list using each node's next property
while (current.next) {
current = current.next;
}
// Append new node to tail
current.next = node;
}
// Return head reference
return head;
};
this.display=function(head){
var start=head;
while(start){
process.stdout.write(start.data+" ");
start=start.next;
}
};
}
function main(){
var T=parseInt(readLine());
var head=null;
var mylist=new Solution();
for(i = 0; i < T; i++){
var data=parseInt(readLine());
head=mylist.insert(head,data);
}
mylist.display(head);
}
#6 Code Example with Python Programming
Code -
Python Programming
class Node:
def __init__(self,data):
self.data = data
self.next = None
class Solution:
def display(self,head):
current = head
while current:
print(current.data,end=' ')
current = current.next
def insert(self, head, data):
if head is None:
head = Node(data)
else:
curr = head
while curr.next:
curr = curr.next
curr.next = Node(data)
return head
mylist= Solution()
T=int(input())
head=None
for i in range(T):
data=int(input())
head=mylist.insert(head,data)
mylist.display(head);