java - 删除单链表中的最后一个元素

Question

我正在制作一个简单的链表，并且正在尝试实现一种允许我删除链表的最后一个节点的方法。在某些时候，我的方法是错误的，我不确定错误在哪里以及如何修复它。这是代码!

public Nodo deleteEnd() {

    Nodo aux;
    if (head == null) {
        throw new NoSuchElementException("Element cant be deleted");

    } else {

        aux = head;

        while (aux.next.next != null) {
            aux = aux.next;
        }

        size--;
    }
    return aux;
}

Answer 1

您需要将最后但并非最不重要的节点的next分配给null:

if(head.next == null) {
    // head is last!
    head = null;
    size = 0;
} else {
    previous = head;
    current = head.next;
    // while current is not last, keep going
    while(current.next != null) {
       previous = current;
       current = current.next;
    }
    // current is now on last!
    previous.next = null;
    size--;
}