# Program To Create A Singly Linked List Of N Nodes And Count The Number Of Nodes

Program To Create A Singly Linked List Of N Nodes And Count The Number Of Nodes on fibonacci, factorial, prime, armstrong, swap, reverse, search, sort, stack, queue, array, linkedlist, tree, graph etc.

## Program to create a singly linked list of n nodes and count the number of nodes

### Explanation

In this program, we need to create a singly linked list and count the nodes present in the list.

To accomplish this task, traverse through the list using node current which initially points to head. Increment current in such a way that current will point to its next node in each iteration and increment variable count by 1. In the end, the count will hold the value which denotes the number of nodes present in the list.

### Algorithm

1. Create a class Node which has two attributes: data and next. Next is a pointer to the next node in the list.
2. Create another class which has two attributes: head and tail.
1. Create a new node.
2. It first checks, whether the head is equal to null which means the list is empty.
3. If the list is empty, both head and tail will point to the newly added node.
4. If the list is not empty, the new node will be added to end of the list such that tail's next will point to a newly added node. This new node will become the new tail of the list.
4. countNodes() will count the nodes present in the list:
1. Define a node current which will initially point to the head of the list.
2. Declare and initialize a variable count to 0.
3. Traverse through the list till current point to null.
4. Increment the value of count by 1 for each node encountered in the list.
5. display() will display the nodes present in the list:
1. Define a node current which will initially point to the head of the list.
2. Traverse through the list till current points to null.
3. Display each node by making current to point to node next to it in each iteration.

### Python

```#Represent a node of the singly linked list
class Node:
def __init__(self,data):
self.data = data;
self.next = None;

class CountNodes:
def __init__(self):
self.tail = None;

#Create a new node
newNode = Node(data);

#Checks if the list is empty
#If list is empty, both head and tail will point to new node
self.tail = newNode;
else:
#newNode will be added after tail such that tail's next will point to newNode
self.tail.next = newNode;
#newNode will become new tail of the list
self.tail = newNode;

#countNodes() will count the nodes present in the list
def countNodes(self):
count = 0;
#Node current will point to head

while(current != None):
#Increment the count by 1 for each node
count = count + 1;
current = current.next;
return count;

#display() will display all the nodes present in the list
def display(self):
#Node current will point to head

print("List is empty");
return;
print("Nodes of singly linked list: ");
while(current != None):
#Prints each node by incrementing pointer
print(current.data),
current = current.next;

sList = CountNodes();

#Displays the nodes present in the list
sList.display();

#Counts the nodes present in the given list
print("Count of nodes present in the list: " + str(sList.countNodes()));
```

Output:

``` Nodes of singly linked list:
1 2 3 4
Count of nodes present in the list: 4
```

### C

```#include <stdio.h>

//Represent a node of singly linked list
struct node{
int data;
struct node *next;
};

struct node *head, *tail = NULL;

//Create a new node
struct node *newNode = (struct node*)malloc(sizeof(struct node));
newNode->data = data;
newNode->next = NULL;

//Checks if the list is empty
//If list is empty, both head and tail will point to new node
tail = newNode;
}
else {
//newNode will be added after tail such that tail's next will point to newNode
tail->next = newNode;
//newNode will become new tail of the list
tail = newNode;
}
}

//countNodes() will count the nodes present in the list
int countNodes() {
int count = 0;
//Node current will point to head

while(current != NULL) {
//Increment the count by 1 for each node
count++;
current = current->next;
}
return count;
}

//display() will display all the nodes present in the list
void display() {
//Node current will point to head

printf("List is empty\n");
return;
}
printf("Nodes of singly linked list: \n");
while(current != NULL) {
//Prints each node by incrementing pointer
printf("%d ", current->data);
current = current->next;
}
printf("\n");
}

int main()
{

//Displays the nodes present in the list
display();

//Counts the nodes present in the given list
printf("Count of nodes present in the list: %d", countNodes());

return 0;
}
```

Output:

```Nodes of singly linked list:
1 2 3 4
Count of nodes present in the list: 4
```

### JAVA

```public class CountNodes {

//Represent a node of singly linked list
class Node{
int data;
Node next;

public Node(int data) {
this.data = data;
this.next = null;
}
}

public Node tail = null;

//Create a new node
Node newNode = new Node(data);

//Checks if the list is empty
//If list is empty, both head and tail will point to new node
tail = newNode;
}
else {
//newNode will be added after tail such that tail's next will point to newNode
tail.next = newNode;
//newNode will become new tail of the list
tail = newNode;
}
}

//countNodes() will count the nodes present in the list
public int countNodes() {
int count = 0;
//Node current will point to head

while(current != null) {
//Increment the count by 1 for each node
count++;
current = current.next;
}
return count;
}

//display() will display all the nodes present in the list
public void display() {
//Node current will point to head
System.out.println("List is empty");
return;
}
System.out.println("Nodes of singly linked list: ");
while(current != null) {
//Prints each node by incrementing pointer
System.out.print(current.data + " ");
current = current.next;
}
System.out.println();
}

public static void main(String[] args) {

CountNodes sList = new CountNodes();

//Displays the nodes present in the list
sList.display();

//Counts the nodes present in the given list
System.out.println("Count of nodes present in the list: " + sList.countNodes());
}
}
```

Output:

```Nodes of the singly linked list:
1 2 3 4
Count of nodes present in the list: 4
```

### C#

```using System;

public class CountNodes
{
//Represent a node of singly linked list
public class Node<T>{
public T data;
public Node<T> next;

public Node(T value) {
data = value;
next = null;
}
}

public Node<T> tail = null;

//Create a new node
Node<T> newNode = new Node<T>(data);

//Checks if the list is empty
//If list is empty, both head and tail will point to new node
tail = newNode;
}
else {
//newNode will be added after tail such that tail's next will point to newNode
tail.next = newNode;
//newNode will become new tail of the list
tail = newNode;
}
}

//countNodes() will count the nodes present in the list
public int countNodes() {
int count = 0;
//Node current will point to head

while(current != null) {
//Increment the count by 1 for each node
count++;
current = current.next;
}
return count;
}

//display() will display all the nodes present in the list
public void display() {
//Node current will point to head

Console.WriteLine("List is empty");
return;
}
Console.WriteLine("Nodes of singly linked list: ");
while(current != null) {
//Prints each node by incrementing pointer
Console.Write(current.data + " ");
current = current.next;
}
Console.WriteLine();
}
}

public static void Main()
{

//Displays the nodes present in the list
sList.display();

//Counts the nodes present in the given list
Console.WriteLine("Count of nodes present in the list: " + sList.countNodes());
}
}
```

Output:

```Nodes of singly linked list:
1 2 3 4
Count of nodes present in the list: 4
```

### PHP

```<!DOCTYPE html>
<html>
<body>
<?php
//Represent a node of singly linked list
class Node{
public \$data;
public \$next;

function __construct(\$data){
\$this->data = \$data;
\$this->next = NULL;
}
}
class CountNodes{
public \$tail;
function __construct(){
\$this->tail = NULL;
}

//Create a new node
\$newNode = new Node(\$data);

//Checks if the list is empty
//If list is empty, both head and tail will point to new node
\$this->tail = \$newNode;
}
else {
//newNode will be added after tail such that tail's next will point to newNode
\$this->tail->next = \$newNode;
//newNode will become new tail of the list
\$this->tail = \$newNode;
}
}

//countNodes() will count the nodes present in the list
function countNodes() {
\$count = 0;
//Node current will point to head

while(\$current != NULL) {
//Increment the count by 1 for each node
\$count++;
\$current = \$current->next;
}
return \$count;
}

//display() will display all the nodes present in the list
function display() {
//Node current will point to head

print("List is empty <br>");
return;
}
print("Nodes of singly linked list: <br>");
while(\$current != NULL) {
//Prints each node by incrementing pointer
print(\$current->data . " ");
\$current = \$current->next;
}
print("<br>");
}
}

\$sList = new CountNodes();

//Displays the nodes present in the list
\$sList->display();

//Counts the nodes present in the given list
print("Count of nodes present in the list: " . \$sList->countNodes());
?>
</body>
</html>
```

Output:

```Nodes of singly linked list:
1 2 3 4
Count of nodes present in the list: 4
```

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