C++链表

梦里梦外; 2022-09-06 00:17 149阅读 0赞

上个简单链表，写的有些难看，现在更改一下

[https://liu-endong.blog.csdn.net/article/details/111934018][https_liu-endong.blog.csdn.net_article_details_111934018]

添加了删除尾结点，添加了删除头结点

#include <stdio.h>
    #include<malloc.h>
    
    #define LEN sizeof(struct List)
    
    #if 1   //1开启 0关闭  VS2019开启 codeblocks关闭
    #define scanf scanf_s
    #endif
    
    
    //定义节点
    struct List
    {
    	int num;
    	struct List* next;
    };
    
    struct List* creat()
    {
    	struct List* head = (struct List*)malloc(LEN);
    	head->num = 0;  //存储链表长度，理论上头结点不需要数据域
    	head->next = NULL;
    	return head; 
    }
    
    //尾插法加一个节点
    struct List* addList(List* head, int num)
    {
    	struct List* p;
    	p = head;
    	while (p->next)
    	{
    		p = p->next;
    	}
    	p->next = (struct List*)malloc(LEN);
    	p->next->num = num;
    	p->next->next = NULL;
    	head->num++;
    	printf("加入一个节点后链表长度 %d \n", head->num);
    	return head;
    }
    
    //按存储的数据删除一个节点
    struct List* deleteList(List* head, int num)
    {
    	struct List* p1, *p2;
    	p1 = p2 = head;
    	while (p1->next)
    	{
    		p2 = p1;
    		p1 = p1->next;
    		if (p1->num == num)
    		{
    			p2->next = p1->next;
    			break;
    		}
    	}
    	return head;
    }
    
    //删除尾巴节点
    struct List* deleteTail(List* head)
    {
    	struct List* p1, *p2;
    	p1 = p2 = head->next;
    	while (p1->next)
    	{
    		p2 = p1;
    		p1 = p1->next;
    	}
    	p2->next= NULL;
    	return head;
    }
    
    //删除头节点
    struct List* deleteHead(List* head)
    {
    	if (head->next)
    	{
    		head->next = head->next->next;
    	}
    	return head;
    }
    
    
    //遍历链表
    void print(struct List* head)
    {
    	struct List* p;
    	p = head->next;
    	while (p != NULL)
    	{
    		printf("%d\n", p->num);
    		p = p->next;
    	}
    }
    
    int main()
    {
    	struct List* p;  //初始化一个链表
    	p = creat();  //调用创建函数来创建一个链表
    	deleteHead(p);
    	print(p);
    	printf("\n");
    	p = addList(p, 1);  //从尾巴添加一个10
    	p = addList(p, 2);  //从尾巴添加一个10
    	p = addList(p, 3);  //从尾巴添加一个10
    	p = addList(p, 4);  //从尾巴添加一个10
    	p = addList(p, 5);  //从尾巴添加一个10
    	p = addList(p, 6);  //从尾巴添加一个10
    	p = addList(p, 7);  //从尾巴添加一个10
    	p = addList(p, 8);  //从尾巴添加一个10
    	p = addList(p, 9);  //从尾巴添加一个10
    	p = addList(p, 10);  //从尾巴添加一个10
    	print(p);
    	printf("\n");
    	p = deleteList(p, 3);   //删除元素为3的节点
    	print(p);
    	printf("\n");
    
    	deleteTail(p);
    	print(p);
    	printf("\n");
    	deleteHead(p);
    	print(p);
    }

[https_liu-endong.blog.csdn.net_article_details_111934018]: https://liu-endong.blog.csdn.net/article/details/111934018