Eliminar el nodo n del final de la lista

Lectura

Eliminar el nodo n del final de la lista(Java, Python, PHP, C++, Javascript)

Dada una lista enlazada, elimine el nodo en la posición n contando desde el final, y retorne la lista modificada.

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Código de la solución

Java

class Solution {
    public ListNode removeNthFromEnd(ListNode head, int n) {
        ListNode dummy = new ListNode(0);
        dummy.next = head;
        ListNode fast = dummy;
        ListNode slow = dummy;

        for (int i = 0; i <= n; i++) {
            fast = fast.next;
        }

        while (fast != null) {
            fast = fast.next;
            slow = slow.next;
        }

        slow.next = slow.next.next;

        return dummy.next;
    }
}

Python

class Solution(object):
    def removeNthFromEnd(self, head, n):
        dummy = ListNode(0)
        dummy.next = head
        fast = dummy
        slow = dummy

        for _ in range(n + 1):
            fast = fast.next

        while fast:
            fast = fast.next
            slow = slow.next

        slow.next = slow.next.next

        return dummy.next

PHP

class Solution {

    /**
     * @param ListNode $head
     * @param Integer $n
     * @return ListNode
     */
    function removeNthFromEnd($head, $n) {
        $dummy = new ListNode(0);
        $dummy->next = $head;
        $fast = $dummy;
        $slow = $dummy;

        for ($i = 0; $i <= $n; $i++) {
            $fast = $fast->next;
        }

        while ($fast !== null) {
            $fast = $fast->next;
            $slow = $slow->next;
        }

        $slow->next = $slow->next->next;

        return $dummy->next;
    }
}

C++

class Solution {
public:
    ListNode* removeNthFromEnd(ListNode* head, int n) {
        ListNode dummy(0);
        dummy.next = head;
        ListNode* fast = &dummy;
        ListNode* slow = &dummy;

        for (int i = 0; i <= n; i++) {
            fast = fast->next;
        }

        while (fast != nullptr) {
            fast = fast->next;
            slow = slow->next;
        }

        ListNode* toDelete = slow->next;
        slow->next = slow->next->next;
        delete toDelete;

        return dummy.next;
    }
};

JavaScript

/**
 * @param {ListNode} head
 * @param {number} n
 * @return {ListNode}
 */
var removeNthFromEnd = function(head, n) {
    let dummy = new ListNode(0);
    dummy.next = head;
    let fast = dummy;
    let slow = dummy;

    for (let i = 0; i <= n; i++) {
        fast = fast.next;
    }

    while (fast !== null) {
        fast = fast.next;
        slow = slow.next;
    }

    slow.next = slow.next.next;

    return dummy.next;
};