Delete duplicate-value nodes from a sorted linked list
Problem Statement :
This challenge is part of a tutorial track by MyCodeSchool You are given the pointer to the head node of a sorted linked list, where the data in the nodes is in ascending order. Delete nodes and return a sorted list with each distinct value in the original list. The given head pointer may be null indicating that the list is empty. Example head refers to the first node in the list 1 -> 2 -> 2- > 3 -> 3 -> 3 -> 3 -> NULL. Remove 1 of the 2 data values and return pointing to the revised list 1 -> 2 -> 3 -> NULL. Function Description Complete the removeDuplicates function in the editor below. removeDuplicates has the following parameter: SinglyLinkedListNode pointer head: a reference to the head of the list Returns SinglyLinkedListNode pointer: a reference to the head of the revised list Input Format The first line contains an integer t, the number of test cases. The format for each test case is as follows: The first line contains an integer n, the number of elements in the linked list. Each of the next n lines contains an integer, the data value for each of the elements of the linked list.
Solution :
Solution in C :
In C++ :
/*
Remove all duplicate elements from a sorted linked list
Node is defined as
struct Node
{
int data;
struct Node *next;
}
*/
Node* RemoveDuplicates(Node *head)
{
// This is a "method-only" submission.
// You only need to complete this method.
Node *ptr = head,*temp=NULL,*tmp=NULL;
while(ptr!=NULL && ptr->next!=NULL)
{
temp = ptr->next;
ptr->next=NULL;
while(temp!=NULL && ptr->data == temp->data)
{
tmp=temp;
temp=temp->next;
tmp->next=NULL;
delete(tmp);
}
ptr->next = temp;
ptr = temp;
}
return head;
}
In Java :
Node RemoveDuplicates(Node head) {
// This is a "method-only" submission.
// You only need to complete this method.
if(head==null)
return null;
Node temp=head.next;
Node prev=head;
while(temp!=null)
{
if(prev.data==temp.data)
{
prev.next=temp.next;
temp.next=null;
temp=prev.next;
}
else
{
prev=temp;
temp=temp.next;
}
}
return head;
}
In python3 :
"""
Delete duplicate nodes
head could be None as well for empty list
Node is defined as
class Node(object):
def __init__(self, data=None, next_node=None):
self.data = data
self.next = next_node
return back the head of the linked list in the below method.
"""
def RemoveDuplicates(head):
c = head
p = None
if c==None or c.next==None:
return(head)
else:
p=c
c=c.next
while c!= None:
if p.data==c.data:
p.next = c.next
c=c.next
else:
p = p.next
c = c.next
return(head)
In C :
// Complete the removeDuplicates function below.
/*
* For your reference:
*
* SinglyLinkedListNode {
* int data;
* SinglyLinkedListNode* next;
* };
*
*/
SinglyLinkedListNode* removeDuplicates(SinglyLinkedListNode* head) {
struct SinglyLinkedListNode*temp1=head;
struct SinglyLinkedListNode*temp=head->next;
while(temp!=NULL)
{
if(head->data==temp->data)
{
temp=temp->next;
head->next=temp;
}
else
{
head=temp;
temp=temp->next;
}
}
return temp1;
}
View More Similar Problems
Get Node Value
This challenge is part of a tutorial track by MyCodeSchool Given a pointer to the head of a linked list and a specific position, determine the data value at that position. Count backwards from the tail node. The tail is at postion 0, its parent is at 1 and so on. Example head refers to 3 -> 2 -> 1 -> 0 -> NULL positionFromTail = 2 Each of the data values matches its distance from the t
View Solution →Delete duplicate-value nodes from a sorted linked list
This challenge is part of a tutorial track by MyCodeSchool You are given the pointer to the head node of a sorted linked list, where the data in the nodes is in ascending order. Delete nodes and return a sorted list with each distinct value in the original list. The given head pointer may be null indicating that the list is empty. Example head refers to the first node in the list 1 -> 2 -
View Solution →Cycle Detection
A linked list is said to contain a cycle if any node is visited more than once while traversing the list. Given a pointer to the head of a linked list, determine if it contains a cycle. If it does, return 1. Otherwise, return 0. Example head refers 1 -> 2 -> 3 -> NUL The numbers shown are the node numbers, not their data values. There is no cycle in this list so return 0. head refer
View Solution →Find Merge Point of Two Lists
This challenge is part of a tutorial track by MyCodeSchool Given pointers to the head nodes of 2 linked lists that merge together at some point, find the node where the two lists merge. The merge point is where both lists point to the same node, i.e. they reference the same memory location. It is guaranteed that the two head nodes will be different, and neither will be NULL. If the lists share
View Solution →Inserting a Node Into a Sorted Doubly Linked List
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. Example head refers to the list 1 <-> 2 <-> 4 - > NULL. data = 3 Return a reference to the new list: 1 <-> 2 <-> 4 - > NULL , Function Description Complete the sortedInsert function
View Solution →Reverse a doubly linked list
This challenge is part of a tutorial track by MyCodeSchool Given the pointer to the head node of a doubly linked list, reverse the order of the nodes in place. That is, change the next and prev pointers of the nodes so that the direction of the list is reversed. Return a reference to the head node of the reversed list. Note: The head node might be NULL to indicate that the list is empty.
View Solution →