输出带头结点单链表的函数

以下是带头结点单链表的函数实现：

#include <stdio.h>
#include <stdlib.h>

typedef struct Node {
    int data;
    struct Node* next;
} Node, *LinkedList;

LinkedList createLinkedList() {
    LinkedList L = (LinkedList)malloc(sizeof(Node));
    L->next = NULL;
    return L;
}

void insert(LinkedList L, int data) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    newNode->data = data;
    newNode->next = L->next;
    L->next = newNode;
}

void delete(LinkedList L, int data) {
    Node* p = L->next;
    Node* pre = L;
    while (p != NULL) {
        if (p->data == data) {
            pre->next = p->next;
            free(p);
            return;
        }
        pre = p;
        p = p->next;
    }
}

void display(LinkedList L) {
    Node* p = L->next;
    while (p != NULL) {
        printf("%d ", p->data);
        p = p->next;
    }
    printf("\n");
}

void destroy(LinkedList L) {
    Node* p = L->next;
    while (p != NULL) {
        Node* next = p->next;
        free(p);
        p = next;
    }
    free(L);
}

int main() {
    LinkedList L = createLinkedList();
    insert(L, 1);
    insert(L, 2);
    insert(L, 3);
    display(L);
    delete(L, 2);
    display(L);
    destroy(L);
    return 0;
}