Question

我试图找出如何删除第一个节点并将其插入到链接的末尾。到目前为止，我能够添加＆＃34; Hello＆＃34;的每个字符。到链表并添加了＆＃34; - ＆＃34;在列表的末尾。我正在试图弄清楚如何在list.h上实现rotate函数。

list.h：

   class list{
    private:
        node *head;
        node *tail;
    public:

        list(){
            head = NULL;
            tail = NULL;
        }

         ~list(){
            if(head == NULL){
                return;
            }
            node *temp = head;
            while(temp != NULL){
                node *next = temp ->next;
                delete temp;
                temp = next;
            }
        }

        void addAtEnd(char x){
            node *temp = new node(x);
            node *curr = head;
            if(head = NULL){
                head = temp;
            }else{
                while(curr->next != NULL){
                   curr = curr->next;
                }
                curr ->next = temp;
            }
        }
        bool isVowel(char ch)
        {
            switch (ch)
            {
                case 'A':
                case 'E':
                case 'I':
                case 'O':
                case 'U':
                case 'Y':
                case 'a':
                case 'e':
                case 'i':
                case 'o':
                case 'u':
                case 'y':
                    return true;
                default:
                    return false;
                }
        }

        void rotate(){
            node *temp = head;
            if(isVowel(temp->n)){
               addAtEnd('-');


            } 
        }

Answer 1

要将第一个元素从单个链接列表移动到最后，您必须：

// Moves one element of a single-linked list from the front to the back
void rotate() {
    if (head && head != tail ) {
        node* tmp = head;            // Store a reference to the first element
        head = head->next;           // Set the head of the list to the second element
        tmp->next = nullptr;         // Detach the removed element from the list
        tail->next = tmp;            // Link the last element to the removed element
        tail = tmp;                  // and update the tail
    }
}

http://coliru.stacked-crooked.com/a/e4d322e13ff655f7

您必须更新tail中的addAtEnd()才能使用它。否则，您总是必须遍历列表才能找到尾部。

如何删除第一个节点并将其插入链接列表C ++的末尾？

1 个答案: