Given a circular singly linked list containing N nodes. The task is to delete all nodes from the list which are prime.
Examples:
Input : 9->11->32->6->13->20
Output : 9 32 6 20Input : 6->11->16->21->17->10
Output : 6 16 21 10
Approach: The idea is to traverse the nodes of the circular singly linked list one by one and get the pointer of the nodes which are prime. Delete those nodes by following the approach used in the post: Delete a node from circular Linked List.
Below is the implementation of the above idea:
C++
// CPP program to delete all prime // node from a Circular singly linked list #include <bits/stdc++.h> using namespace std;
// Structure for a node struct Node {
int data;
struct Node* next;
}; // Function to insert a node at the beginning // of a Circular linked list void push( struct Node** head_ref, int data)
{ struct Node* ptr1
= ( struct Node*) malloc ( sizeof ( struct Node));
struct Node* temp = *head_ref;
ptr1->data = data;
ptr1->next = *head_ref;
// If linked list is not NULL then
// set the next of last node
if (*head_ref != NULL) {
while (temp->next != *head_ref)
temp = temp->next;
temp->next = ptr1;
}
else
ptr1->next = ptr1; // For the first node
*head_ref = ptr1;
} // Delete the node if it is prime void deleteNode(Node* head_ref, Node* del)
{ struct Node *temp = head_ref, *temp2 = head_ref;
// traverse list till not found
// delete node
while (temp->next != del) {
temp = temp->next;
}
// copy address of node
temp->next = del->next;
// Finally, free the memory
// occupied by del
free (del);
return ;
} // Function to check if a number is prime bool isPrime( int n)
{ // Corner cases
if (n <= 1)
return false ;
if (n <= 3)
return true ;
// This is checked so that we can skip
// middle five numbers in below loop
if (n % 2 == 0 || n % 3 == 0)
return false ;
for ( int i = 5; i * i <= n; i = i + 6)
if (n % i == 0 || n % (i + 2) == 0)
return false ;
return true ;
} // Function to delete all prime nodes // from the singly circular linked list Node* deletePrimeNodes(Node* head) { if (head == NULL)
return NULL;
struct Node* ptr = head;
struct Node* temp;
// setting up the head node to the first non prime node
while (isPrime(ptr->data)) {
ptr = ptr->next;
if (ptr == head) {
return NULL;
}
}
temp = ptr;
Node* temp2 = ptr;
ptr = ptr->next;
// setting up the last node next to the first non prime
// node
while (ptr != head) {
temp2 = ptr;
ptr = ptr->next;
}
temp2->next = temp;
head = temp;
ptr = head;
// traverse list till the endl
// if node is prime then delete it
do {
temp = ptr->next;
// if node is prime
if (isPrime(ptr->data))
deleteNode(head, ptr);
ptr = temp;
} while (ptr != head);
return head;
} // Function to print nodes in a // given singly linked list void printList( struct Node* head)
{ if (!head) {
printf ( "NULL" );
}
struct Node* temp = head;
if (head != NULL) {
do {
printf ( "%d " , temp->data);
temp = temp->next;
} while (temp != head);
}
} // Driver code int main()
{ // Initialize lists as empty
struct Node* head = NULL;
// Created linked list will be
// 9->11->32->6->13->20
push(&head, 20);
push(&head, 13);
push(&head, 6);
push(&head, 32);
push(&head, 11);
push(&head, 9);
cout << "Given List : " ;
printList(head);
cout << "\nList After deleting prime nodes : " ;
head = deletePrimeNodes(head);
printList(head);
return 0;
} |
Java
// Java program to delete all prime // node from a Circular singly linked list class GFG
{ // Structure for a node static class Node
{ int data;
Node next;
}; // Function to insert a node at the beginning // of a Circular linked list static Node push(Node head_ref, int data)
{ Node ptr1 = new Node();
Node temp = head_ref;
ptr1.data = data;
ptr1.next = head_ref;
// If linked list is not null then
// set the next of last node
if (head_ref != null )
{
while (temp.next != head_ref)
temp = temp.next;
temp.next = ptr1;
}
else
ptr1.next = ptr1; // For the first node
head_ref = ptr1;
return head_ref;
} // Delete the node if it is prime static Node deleteNode(Node head_ref, Node del)
{ Node temp = head_ref;
// If node to be deleted is head node
if (head_ref == del)
head_ref = del.next;
// traverse list till not found
// delete node
while (temp.next != del)
{
temp = temp.next;
}
// copy address of node
temp.next = del.next;
return head_ref;
} // Function to check if a number is prime static boolean isPrime( int n)
{ // Corner cases
if (n <= 1 )
return false ;
if (n <= 3 )
return true ;
// This is checked so that we can skip
// middle five numbers in below loop
if (n % 2 == 0 || n % 3 == 0 )
return false ;
for ( int i = 5 ; i * i <= n; i = i + 6 )
if (n % i == 0 || n % (i + 2 ) == 0 )
return false ;
return true ;
} // Function to delete all prime nodes // from the singly circular linked list static Node deletePrimeNodes(Node head)
{ Node ptr = head;
Node next;
// traverse list till the endl
// if node is prime then delete it
do
{
// if node is prime
if (isPrime(ptr.data))
deleteNode(head, ptr);
// point to next node
next = ptr.next;
ptr = next;
}
while (ptr != head);
return head;
} // Function to print nodes in a // given singly linked list static void printList(Node head)
{ Node temp = head;
if (head != null )
{
do
{
System.out.printf( "%d " , temp.data);
temp = temp.next;
}
while (temp != head);
}
} // Driver code public static void main(String args[])
{ // Initialize lists as empty
Node head = null ;
// Created linked list will be
// 9.11.32.6.13.20
head=push(head, 20 );
head=push(head, 13 );
head=push(head, 6 );
head=push(head, 32 );
head=push(head, 11 );
head=push(head, 9 );
System.out.println( "Given List : " );
printList(head);
System.out.println( "\nList After deleting prime nodes : " );
head=deletePrimeNodes(head);
printList(head);
} } // This code is contributed by Arnab Kundu |
Python3
# Python3 program to delete all prime # node from a Circular singly linked list import math
# Structure for a node class Node:
def __init__( self , data):
self .data = data
self . next = None
# Function to insert a node at the # beginning of a Circular linked list def push(head_ref, data):
ptr1 = Node(data)
temp = head_ref
ptr1.data = data
ptr1. next = head_ref
# If linked list is not None then
# set the next of last node
if (head_ref ! = None ) :
while (temp. next ! = head_ref):
temp = temp. next
temp. next = ptr1
else :
ptr1. next = ptr1 # For the first node
head_ref = ptr1
return head_ref
# Delete the node if it is prime def deleteNode(head_ref, delete):
temp = head_ref
# If node to be deleted is head node
if (head_ref = = delete):
head_ref = delete. next
# traverse list till not found
# delete node
while (temp. next ! = delete):
temp = temp. next
# copy address of node
temp. next = delete. next
# Finally, free the memory
# occupied by delete
# free(delete)
return head_ref
# Function to check if a number is prime def isPrime(n):
# Corner cases
if (n < = 1 ):
return False
if (n < = 3 ):
return True
# This is checked so that we can skip
# middle five numbers in below loop
if (n % 2 = = 0 or n % 3 = = 0 ):
return False
for i in range ( 5 , n + 1 , 6 ):
if (i * i < n + 2 and
(n % i = = 0 or
n % (i + 2 ) = = 0 )):
return False
return True
# Function to delete all prime nodes # from the singly circular linked list def deletePrimeNodes( head):
ptr = head
#next
# traverse list till the endl
# if node is prime then delete it
# if (isPrime(ptr.data)!=True):
# deleteNode(head, ptr)
# point to next node
next = ptr. next
ptr = next
while (ptr ! = head):
# if node is prime
if (isPrime(ptr.data) = = True ):
deleteNode(head, ptr)
# point to next node
next = ptr. next
ptr = next
return head
# Function to print nodes in a # given singly linked list def printList(head):
temp = head
if (head ! = None ) :
print (temp.data, end = " " )
temp = temp. next
while (temp ! = head):
print (temp.data, end = " " )
temp = temp. next
# Driver code if __name__ = = '__main__' :
# Initialize lists as empty
head = None
# Created linked list will be
# 9.11.32.6.13.20
head = push(head, 20 )
head = push(head, 13 )
head = push(head, 6 )
head = push(head, 32 )
head = push(head, 11 )
head = push(head, 9 )
print ( "Given List : " , end = "")
printList(head)
print ( "\nList After deleting" ,
"prime nodes : " , end = "")
head = deletePrimeNodes(head)
printList(head)
# This code is contributed by Srathore |
C#
// C# program to delete all prime // node from a Circular singly linked list using System;
class GFG
{ // Structure for a node public class Node
{ public int data;
public Node next;
}; // Function to insert a node at the beginning // of a Circular linked list static Node push(Node head_ref, int data)
{ Node ptr1 = new Node();
Node temp = head_ref;
ptr1.data = data;
ptr1.next = head_ref;
// If linked list is not null then
// set the next of last node
if (head_ref != null )
{
while (temp.next != head_ref)
temp = temp.next;
temp.next = ptr1;
}
else
ptr1.next = ptr1; // For the first node
head_ref = ptr1;
return head_ref;
} // Delete the node if it is prime static Node deleteNode(Node head_ref, Node del)
{ Node temp = head_ref;
// If node to be deleted is head node
if (head_ref == del)
head_ref = del.next;
// traverse list till not found
// delete node
while (temp.next != del)
{
temp = temp.next;
}
// copy address of node
temp.next = del.next;
return head_ref;
} // Function to check if a number is prime static bool isPrime( int n)
{ // Corner cases
if (n <= 1)
return false ;
if (n <= 3)
return true ;
// This is checked so that we can skip
// middle five numbers in below loop
if (n % 2 == 0 || n % 3 == 0)
return false ;
for ( int i = 5; i * i <= n; i = i + 6)
if (n % i == 0 || n % (i + 2) == 0)
return false ;
return true ;
} // Function to delete all prime nodes // from the singly circular linked list static Node deletePrimeNodes(Node head)
{ Node ptr = head;
Node next;
// traverse list till the endl
// if node is prime then delete it
do
{
// if node is prime
if (isPrime(ptr.data))
deleteNode(head, ptr);
// point to next node
next = ptr.next;
ptr = next;
}
while (ptr != head);
return head;
} // Function to print nodes in a // given singly linked list static void printList(Node head)
{ Node temp = head;
if (head != null )
{
do
{
Console.Write( "{0} " , temp.data);
temp = temp.next;
}
while (temp != head);
}
} // Driver code public static void Main()
{ // Initialize lists as empty
Node head = null ;
// Created linked list will be
// 9.11.32.6.13.20
head=push(head, 20);
head=push(head, 13);
head=push(head, 6);
head=push(head, 32);
head=push(head, 11);
head=push(head, 9);
Console.WriteLine( "Given List : " );
printList(head);
Console.WriteLine( "\nList After deleting prime nodes : " );
head=deletePrimeNodes(head);
printList(head);
} } /* This code contributed by PrinciRaj1992 */ |
Javascript
<script> // JavaScript program to delete all prime // node from a Circular singly linked list // Structure for a node class Node { constructor() {
this .data = 0;
this .next = null ;
}
} // Function to insert a node at the beginning
// of a Circular linked list
function push(head_ref , data) {
var ptr1 = new Node();
var temp = head_ref;
ptr1.data = data;
ptr1.next = head_ref;
// If linked list is not null then
// set the next of last node
if (head_ref != null ) {
while (temp.next != head_ref)
temp = temp.next;
temp.next = ptr1;
} else
ptr1.next = ptr1; // For the first node
head_ref = ptr1;
return head_ref;
}
// Delete the node if it is prime
function deleteNode(head_ref, del) {
var temp = head_ref;
// If node to be deleted is head node
if (head_ref == del)
head_ref = del.next;
// traverse list till not found
// delete node
while (temp.next != del) {
temp = temp.next;
}
// copy address of node
temp.next = del.next;
return head_ref;
}
// Function to check if a number is prime
function isPrime(n) {
// Corner cases
if (n <= 1)
return false ;
if (n <= 3)
return true ;
// This is checked so that we can skip
// middle five numbers in below loop
if (n % 2 == 0 || n % 3 == 0)
return false ;
for (i = 5; i * i <= n; i = i + 6)
if (n % i == 0 || n % (i + 2) == 0)
return false ;
return true ;
}
// Function to delete all prime nodes
// from the singly circular linked list
function deletePrimeNodes(head) {
var ptr = head;
var next;
// traverse list till the endl
// if node is prime then delete it
do {
// if node is prime
if (isPrime(ptr.data))
deleteNode(head, ptr);
// point to next node
next = ptr.next;
ptr = next;
} while (ptr != head);
return head;
}
// Function to print nodes in a
// given singly linked list
function printList(head) {
var temp = head;
if (head != null ) {
do {
document.write( temp.data+ " " );
temp = temp.next;
} while (temp != head);
}
}
// Driver code
// Initialize lists as empty
var head = null ;
// Created linked list will be
// 9.11.32.6.13.20
head = push(head, 20);
head = push(head, 13);
head = push(head, 6);
head = push(head, 32);
head = push(head, 11);
head = push(head, 9);
document.write( "Given List : <br/>" );
printList(head);
document.write(
"<br/>List After deleting prime nodes : <br/>"
);
head = deletePrimeNodes(head);
printList(head);
// This code contributed by aashish1995 </script> |
Output
Given List : 9 11 32 6 13 20 List After deleting prime nodes : 9 32 6 20
Complexity Analysis:
- Time Complexity: O(N * sqrt(N))
- Auxiliary Space: O(1)