Given singly linked list with every node having an additional “arbitrary” pointer that currently points to NULL. We need to make the “arbitrary” pointer to the greatest value node in a linked list on its right side.
A Simple Solution is to traverse all nodes one by one. For every node, find the node which has the greatest value on the right side and change the next pointer. The Time Complexity of this solution is O(n2).
An Efficient Solution can work in O(n) time. Below are the steps.
- Reverse the given linked list.
- Start traversing the linked list and store the maximum value node encountered so far. Make arbit of every node to point to max. If the data in the current node is more than the max node so far, update max.
- Reverse modified linked list and return head.
Following is the implementation of the above steps.
C++
// C++ program to point arbit pointers to highest// value on its right#include<bits/stdc++.h>using namespace std;/* Link list node */struct Node{ int data; Node* next, *arbit;};/* Function to reverse the linked list */Node* reverse(Node *head){ Node *prev = NULL, *current = head, *next; while (current != NULL) { next = current->next; current->next = prev; prev = current; current = next; } return prev;}// This function populates arbit pointer in every// node to the greatest value to its right.Node* populateArbit(Node *head){ // Reverse given linked list head = reverse(head); // Initialize pointer to maximum value node Node *max = head; // Traverse the reversed list Node *temp = head->next; while (temp != NULL) { // Connect max through arbit pointer temp->arbit = max; // Update max if required if (max->data < temp->data) max = temp; // Move ahead in reversed list temp = temp->next; } // Reverse modified linked list and return // head. return reverse(head);}// Utility function to print result linked listvoid printNextArbitPointers(Node *node){ printf("Node\tNext Pointer\tArbit Pointer\n"); while (node!=NULL) { cout << node->data << "\t\t"; if (node->next) cout << node->next->data << "\t\t"; else cout << "NULL" << "\t\t"; if (node->arbit) cout << node->arbit->data; else cout << "NULL"; cout << endl; node = node->next; }}/* Function to create a new node with given data */Node *newNode(int data){ Node *new_node = new Node; new_node->data = data; new_node->next = NULL; return new_node;}/* Driver program to test above functions*/int main(){ Node *head = newNode(5); head->next = newNode(10); head->next->next = newNode(2); head->next->next->next = newNode(3); head = populateArbit(head); printf("Resultant Linked List is: \n"); printNextArbitPointers(head); return 0;} |
Java
// Java program to point arbit pointers to highest // value on its right class GfG { /* Link list node */static class Node { int data; Node next, arbit; }/* Function to reverse the linked list */static Node reverse(Node head) { Node prev = null, current = head, next = null; while (current != null) { next = current.next; current.next = prev; prev = current; current = next; } return prev; } // This function populates arbit pointer in every // node to the greatest value to its right. static Node populateArbit(Node head) { // Reverse given linked list head = reverse(head); // Initialize pointer to maximum value node Node max = head; // Traverse the reversed list Node temp = head.next; while (temp != null) { // Connect max through arbit pointer temp.arbit = max; // Update max if required if (max.data < temp.data) max = temp; // Move ahead in reversed list temp = temp.next; } // Reverse modified linked list and return // head. return reverse(head); } // Utility function to print result linked list static void printNextArbitPointers(Node node) { System.out.println("Node\tNext Pointer\tArbit Pointer"); while (node != null) { System.out.print(node.data + "\t\t"); if (node.next != null) System.out.print(node.next.data + "\t\t"); else System.out.print("NULL" +"\t\t"); if (node.arbit != null) System.out.print(node.arbit.data); else System.out.print("NULL"); System.out.println(); node = node.next; } } /* Function to create a new node with given data */static Node newNode(int data) { Node new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code*/public static void main(String[] args) { Node head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); head = populateArbit(head); System.out.println("Resultant Linked List is: "); printNextArbitPointers(head); }} // This code is contributed by Prerna Saini. |
Python
# Python Program to point arbit pointers to highest# value on its right# Node class class Node: # Constructor to initialize the node object def __init__(self, data): self.data = data self.next = None self.arbit = None# Function to reverse the linked list def reverse(head): prev = None current = head next = None while (current != None): next = current.next current.next = prev prev = current current = next return prev# This function populates arbit pointer in every# node to the greatest value to its right.def populateArbit(head): # Reverse given linked list head = reverse(head) # Initialize pointer to maximum value node max = head # Traverse the reversed list temp = head.next while (temp != None): # Connect max through arbit pointer temp.arbit = max # Update max if required if (max.data < temp.data): max = temp # Move ahead in reversed list temp = temp.next # Reverse modified linked list and return # head. return reverse(head)# Utility function to print result linked listdef printNextArbitPointers(node): print("Node\tNext Pointer\tArbit Pointer\n") while (node != None): print( node.data , "\t\t",end = "") if (node.next != None): print( node.next.data , "\t\t",end = "") else : print( "None" , "\t\t",end = "") if (node.arbit != None): print( node.arbit.data,end = "") else : print( "None",end = "") print("\n") node = node.next # Function to create a new node with given data def newNode(data): new_node = Node(0) new_node.data = data new_node.next = None return new_node# Driver codehead = newNode(5)head.next = newNode(10)head.next.next = newNode(2)head.next.next.next = newNode(3)head = populateArbit(head)print("Resultant Linked List is: \n")printNextArbitPointers(head)# This code is contributed by Arnab Kundu |
C#
// C# program to point arbit pointers // to highest value on its rightusing System;class GfG { /* Link list node */ class Node { public int data; public Node next, arbit; } /* Function to reverse the linked list */ static Node reverse(Node head) { Node prev = null, current = head, next = null; while (current != null) { next = current.next; current.next = prev; prev = current; current = next; } return prev; } // This function populates arbit pointer in every // node to the greatest value to its right. static Node populateArbit(Node head) { // Reverse given linked list head = reverse(head); // Initialize pointer to maximum value node Node max = head; // Traverse the reversed list Node temp = head.next; while (temp != null) { // Connect max through arbit pointer temp.arbit = max; // Update max if required if (max.data < temp.data) max = temp; // Move ahead in reversed list temp = temp.next; } // Reverse modified linked list // and return head. return reverse(head); } // Utility function to print result linked list static void printNextArbitPointers(Node node) { Console.WriteLine("Node\tNext Pointer\tArbit Pointer"); while (node != null) { Console.Write(node.data + "\t\t"); if (node.next != null) Console.Write(node.next.data + "\t\t"); else Console.Write("NULL" +"\t\t"); if (node.arbit != null) Console.Write(node.arbit.data); else Console.Write("NULL"); Console.WriteLine(); node = node.next; } } /* Function to create a new node with given data */ static Node newNode(int data) { Node new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code*/ public static void Main(String[] args) { Node head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); head = populateArbit(head); Console.WriteLine("Resultant Linked List is: "); printNextArbitPointers(head); }}/* This code is contributed by 29AjayKumar */ |
Javascript
<script>// javascript program to point arbit pointers to highest // value on its right /* Link list node */ class Node { constructor(val) { this.data = val; this.arbit = null; this.next = null; } } /* Function to reverse the linked list */ function reverse(head) { var prev = null, current = head, next = null; while (current != null) { next = current.next; current.next = prev; prev = current; current = next; } return prev; } // This function populates arbit pointer in every // node to the greatest value to its right. function populateArbit(head) { // Reverse given linked list head = reverse(head); // Initialize pointer to maximum value node var max = head; // Traverse the reversed list var temp = head.next; while (temp != null) { // Connect max through arbit pointer temp.arbit = max; // Update max if required if (max.data < temp.data) max = temp; // Move ahead in reversed list temp = temp.next; } // Reverse modified linked list and return // head. return reverse(head); } // Utility function to print result linked list function printNextArbitPointers(node) { document.write("Node Next Pointer Arbit Pointer<br/>"); while (node != null) { document.write(node.data + " "); if (node.next != null) document.write(node.next.data + " "); else document.write("NULL" + " "); if (node.arbit != null) document.write(node.arbit.data); else document.write("NULL"); document.write("<br/>"); node = node.next; } } /* Function to create a new node with given data */ function newNode(data) { var new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code */ var head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); head = populateArbit(head); document.write("Resultant Linked List is: <br/>"); printNextArbitPointers(head);// This code is contributed by umadevi9616 </script> |
Output
Resultant Linked List is: Node Next Pointer Arbit Pointer 5 10 10 10 2 3 2 3 3 3 NULL NULL
The time complexity of the reverse function is O(n) as it iterates over each node in the linked list once.
The space complexity of the program is O(1).
Recursive Solution: We can recursively reach the last node and traverse the linked list from the end. The recursive solution doesn’t require reversing of the linked list. We can also use a stack in place of recursion to temporarily hold nodes. Thanks to Santosh Kumar Mishra for providing this solution.
C++
// C++ program to point arbit pointers to highest// value on its right#include<bits/stdc++.h>using namespace std;/* Link list node */struct Node{ int data; Node* next, *arbit;};// This function populates arbit pointer in every// node to the greatest value to its right.void populateArbit(Node *head){ // using static maxNode to keep track of maximum // orbit node address on right side static Node *maxNode; // if head is null simply return the list if (head == NULL) return; /* if head->next is null it means we reached at the last node just update the max and maxNode */ if (head->next == NULL) { maxNode = head; return; } /* Calling the populateArbit to the next node */ populateArbit(head->next); /* updating the arbit node of the current node with the maximum value on the right side */ head->arbit = maxNode; /* if current Node value id greater then the previous right node then update it */ if (head->data > maxNode->data) maxNode = head; return;}// Utility function to print result linked listvoid printNextArbitPointers(Node *node){ printf("Node\tNext Pointer\tArbit Pointer\n"); while (node!=NULL) { cout << node->data << "\t\t"; if(node->next) cout << node->next->data << "\t\t"; else cout << "NULL" << "\t\t"; if(node->arbit) cout << node->arbit->data; else cout << "NULL"; cout << endl; node = node->next; }}/* Function to create a new node with given data */Node *newNode(int data){ Node *new_node = new Node; new_node->data = data; new_node->next = NULL; return new_node;}/* Driver program to test above functions*/int main(){ Node *head = newNode(5); head->next = newNode(10); head->next->next = newNode(2); head->next->next->next = newNode(3); populateArbit(head); printf("Resultant Linked List is: \n"); printNextArbitPointers(head); return 0;} |
Java
// Java program to point arbit pointers to highest// value on its rightclass GfG{ /* Link list node */ static class Node { int data; Node next, arbit; } static Node maxNode; // This function populates arbit pointer in every // node to the greatest value to its right. static void populateArbit(Node head) { // if head is null simply return the list if (head == null) return; /* if head->next is null it means we reached at the last node just update the max and maxNode */ if (head.next == null) { maxNode = head; return; } /* Calling the populateArbit to the next node */ populateArbit(head.next); /* updating the arbit node of the current node with the maximum value on the right side */ head.arbit = maxNode; /* if current Node value id greater then the previous right node then update it */ if (head.data > maxNode.data) maxNode = head; return; } // Utility function to print result linked list static void printNextArbitPointers(Node node) { System.out.println("Node\tNext Pointer\tArbit Pointer"); while (node != null) { System.out.print(node.data + "\t\t\t"); if (node.next != null) System.out.print(node.next.data + "\t\t\t\t"); else System.out.print("NULL" +"\t\t\t"); if (node.arbit != null) System.out.print(node.arbit.data); else System.out.print("NULL"); System.out.println(); node = node.next; } } /* Function to create a new node with given data */ static Node newNode(int data) { Node new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code*/ public static void main(String[] args) { Node head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); populateArbit(head); System.out.println("Resultant Linked List is: "); printNextArbitPointers(head); }}// This code is contributed by shubham96301 |
Python3
# Python3 program to point arbit pointers to highest # value on its right ''' Link list node '''# Node class class newNode: # Constructor to initialize the node object def __init__(self, data): self.data = data self.next = None self.arbit = None# This function populates arbit pointer in every # node to the greatest value to its right. maxNode = newNode(None)def populateArbit(head): # using static maxNode to keep track of maximum # orbit node address on right side global maxNode # if head is null simply return the list if (head == None): return ''' if head.next is null it means we reached at the last node just update the max and maxNode ''' if (head.next == None): maxNode = head return ''' Calling the populateArbit to the next node ''' populateArbit(head.next) ''' updating the arbit node of the current node with the maximum value on the right side ''' head.arbit = maxNode ''' if current Node value id greater then the previous right node then update it ''' if (head.data > maxNode.data and maxNode.data != None ): maxNode = head return# Utility function to print result linked list def printNextArbitPointers(node): print("Node\tNext Pointer\tArbit Pointer") while (node != None): print(node.data,"\t\t", end = "") if(node.next): print(node.next.data,"\t\t", end = "") else: print("NULL","\t\t", end = "") if(node.arbit): print(node.arbit.data, end = "") else: print("NULL", end = "") print() node = node.next ''' Driver code'''head = newNode(5) head.next = newNode(10) head.next.next = newNode(2) head.next.next.next = newNode(3) populateArbit(head) print("Resultant Linked List is:") printNextArbitPointers(head) # This code is contributed by SHUBHAMSINGH10 |
C#
// C# program to point arbit pointers to highest// value on its rightusing System; class GfG{ /* Link list node */ public class Node { public int data; public Node next, arbit; } static Node maxNode; // This function populates arbit pointer in every // node to the greatest value to its right. static void populateArbit(Node head) { // if head is null simply return the list if (head == null) return; /* if head->next is null it means we reached at the last node just update the max and maxNode */ if (head.next == null) { maxNode = head; return; } /* Calling the populateArbit to the next node */ populateArbit(head.next); /* updating the arbit node of the current node with the maximum value on the right side */ head.arbit = maxNode; /* if current Node value id greater then the previous right node then update it */ if (head.data > maxNode.data) maxNode = head; return; } // Utility function to print result linked list static void printNextArbitPointers(Node node) { Console.WriteLine("Node\tNext Pointer\tArbit Pointer"); while (node != null) { Console.Write(node.data + "\t\t\t"); if (node.next != null) Console.Write(node.next.data + "\t\t\t\t"); else Console.Write("NULL" +"\t\t\t"); if (node.arbit != null) Console.Write(node.arbit.data); else Console.Write("NULL"); Console.WriteLine(); node = node.next; } } /* Function to create a new node with given data */ static Node newNode(int data) { Node new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code*/ public static void Main(String[] args) { Node head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); populateArbit(head); Console.WriteLine("Resultant Linked List is: "); printNextArbitPointers(head); }}/* This code contributed by PrinciRaj1992 */ |
Javascript
<script>// Javascript program to point// arbit pointers to highest// value on its right /* Link list node */ class Node { constructor() { this.data = 0; this.arbit = null; this.next = null; } } var maxNode; // This function populates arbit pointer in every // node to the greatest value to its right. function populateArbit(head) { // if head is null simply return the list if (head == null) return; /* if head->next is null it means we reached at the last node just update the max and maxNode */ if (head.next == null) { maxNode = head; return; } /* Calling the populateArbit to the next node */ populateArbit(head.next); /* updating the arbit node of the current node with the maximum value on the right side */ head.arbit = maxNode; /* if current Node value id greater then the previous right node then update it */ if (head.data > maxNode.data) maxNode = head; return; } // Utility function to print result linked list function printNextArbitPointers(node) { document.write( "Node Next Pointer Arbit Pointer<br/>" ); while (node != null) { document.write(node.data + " "); if (node.next != null) document.write(node.next.data + " "); else document.write("NULL" + " "); if (node.arbit != null) document.write(node.arbit.data); else document.write("NULL"); document.write("<br/>"); node = node.next; } } /* Function to create a new node with given data */ function newNode(data) {var new_node = new Node(); new_node.data = data; new_node.next = null; return new_node; } /* Driver code */ var head = newNode(5); head.next = newNode(10); head.next.next = newNode(2); head.next.next.next = newNode(3); populateArbit(head); document.write("Resultant Linked List is: <br/>"); printNextArbitPointers(head);// This code contributed by gauravrajput1</script> |
Output
Resultant Linked List is: Node Next Pointer Arbit Pointer 5 10 10 10 2 3 2 3 3 3 NULL NULL
The time complexity of this program is O(n), where n is the length of the linked list.
The space complexity of this program is also O(n), where n is the length of the linked list.
This article is contributed by Aditya Goel. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above
Feeling lost in the world of random DSA topics, wasting time without progress? It’s time for a change! Join our DSA course, where we’ll guide you on an exciting journey to master DSA efficiently and on schedule.
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 neveropen!
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 neveropen!
