Dada una lista vinculada, la tarea es eliminar el primer Node de la lista vinculada y actualizar el puntero principal de la lista vinculada.
Ejemplos:
Input : 1 -> 2 -> 3 -> 4 -> 5 -> NULL Output : 2 -> 3 -> 4 -> 5 -> NULL Input : 2 -> 4 -> 6 -> 8 -> 33 -> 67 -> NULL Output : 4 -> 6 -> 8 -> 33 -> 67 -> NULL
Para eliminar el primer Node, debemos hacer que el segundo Node sea el encabezado y eliminar la memoria asignada para el primer Node.
C++
// CPP program to remove first node of
// linked list.
#include <iostream>
using namespace std;
/* Link list node */
struct Node {
int data;
struct Node* next;
};
/* Function to remove the first node
of the linked list */
Node* removeFirstNode(struct Node* head)
{
if (head == NULL)
return NULL;
// Move the head pointer to the next node
Node* temp = head;
head = head->next;
delete temp;
return head;
}
// Function to push node at head
void push(struct Node** head_ref, int new_data)
{
struct Node* new_node = new Node;
new_node->data = new_data;
new_node->next = (*head_ref);
(*head_ref) = new_node;
}
// Driver code
int main()
{
/* Start with the empty list */
Node* head = NULL;
/* Use push() function to construct
the below list 8 -> 23 -> 11 -> 29 -> 12 */
push(&head, 12);
push(&head, 29);
push(&head, 11);
push(&head, 23);
push(&head, 8);
head = removeFirstNode(head);
for (Node* temp = head; temp != NULL; temp = temp->next)
cout << temp->data << " ";
return 0;
}
Java
// Java program to remove first node of
// linked list.
class GFG {
// Link list node /
static class Node {
int data;
Node next;
};
// Function to remove the first node
// of the linked list /
static Node removeFirstNode(Node head)
{
if (head == null)
return null;
// Move the head pointer to the next node
Node temp = head;
head = head.next;
return head;
}
// Function to push node at head
static Node push(Node head_ref, int new_data)
{
Node new_node = new Node();
new_node.data = new_data;
new_node.next = (head_ref);
(head_ref) = new_node;
return head_ref;
}
// Driver code
public static void main(String args[])
{
// Start with the empty list /
Node head = null;
// Use push() function to con
// the below list 8 . 23 . 11 . 29 . 12 /
head = push(head, 12);
head = push(head, 29);
head = push(head, 11);
head = push(head, 23);
head = push(head, 8);
head = removeFirstNode(head);
for (Node temp = head; temp != null; temp = temp.next)
System.out.print(temp.data + " ");
}
}
// This code is contributed by Arnab Kundu
Python3
# Python3 program to remove first node of
# linked list.
import sys
# Link list node
class Node:
def __init__(self, data):
self.data = data
self.next = None
# Function to remove the first node
# of the linked list
def removeFirstNode(head):
if not head:
return None
temp = head
# Move the head pointer to the next node
head = head.next
temp = None
return head
# Function to push node at head
def push(head, data):
if not head:
return Node(data)
temp = Node(data)
temp.next = head
head = temp
return head
# Driver code
if __name__=='__main__':
# Start with the empty list
head = None
# Use push() function to construct
# the below list 8 -> 23 -> 11 -> 29 -> 12
head = push(head, 12)
head = push(head, 29)
head = push(head, 11)
head = push(head, 23)
head = push(head, 8)
head = removeFirstNode(head)
while(head):
print("{} ".format(head.data), end ="")
head = head.next
# This code is Contributed by Vikash Kumar 37
C#
// C# program to remove first node of
// linked list.
using System;
class GFG
{
// Link list node /
public class Node
{
public int data;
public Node next;
};
// Function to remove the first node
// of the linked list /
static Node removeFirstNode(Node head)
{
if (head == null)
return null;
// Move the head pointer to the next node
Node temp = head;
head = head.next;
return head;
}
// Function to push node at head
static Node push(Node head_ref, int new_data)
{
Node new_node = new Node();
new_node.data = new_data;
new_node.next = (head_ref);
(head_ref) = new_node;
return head_ref;
}
// Driver code
public static void Main(String []args)
{
// Start with the empty list /
Node head = null;
// Use push() function to con
// the below list 8 . 23 . 11 . 29 . 12 /
head = push(head, 12);
head = push(head, 29);
head = push(head, 11);
head = push(head, 23);
head = push(head, 8);
head = removeFirstNode(head);
for (Node temp = head; temp != null; temp = temp.next)
Console.Write(temp.data + " ");
}
}
/* This code contributed by PrinciRaj1992 */
Javascript
<script>
// javascript program to remove first node of
// linked list.
// Link list node /
class Node {
constructor(val) {
this.data = val;
this.next = null;
}
}
// Function to remove the first node
// of the linked list /
function removeFirstNode( head) {
if (head == null)
return null;
// Move the head pointer to the next node
temp = head;
head = head.next;
return head;
}
// Function to push node at head
function push( head_ref , new_data) {
new_node = new Node();
new_node.data = new_data;
new_node.next = (head_ref);
(head_ref) = new_node;
return head_ref;
}
// Driver code
// Start with the empty list /
head = null;
// Use push() function to con
// the below list 8 . 23 . 11 . 29 . 12 /
head = push(head, 12);
head = push(head, 29);
head = push(head, 11);
head = push(head, 23);
head = push(head, 8);
head = removeFirstNode(head);
for ( temp = head; temp != null; temp = temp.next)
document.write(temp.data + " ");
// This code is contributed by todaysgaurav
</script>
Producción:
23 11 29 12
Complejidad del tiempo : O(1)
Publicación traducida automáticamente
Artículo escrito por gfg_sal_gfg y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA