C 单向链表(带头节点)

链表的头节点初始化

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

typedef struct Node
{
	int data;
	struct Node *next;
}Link;

Link *initLink()
{
	Link *head = (Link *)malloc(sizeof(Link));
	if(head != NULL)
	{
		head->data = 0;
		head->next = NULL;
		return head;
	}
	return NULL;
}

int main()
{
	Link *head = initLink();
	if(head == NULL)
	{
		exit(0);
	}
	return 0;
}

头插法插入新节点形成链表

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

typedef struct Node
{
	int data;
	struct Node *next;
}Link;

Link printfLink(Link *head)
{
	Link *point = head->next;
	while(point != NULL)
	{
		printf("%d\t", point->data);
		point = point->next;
	}
	putchar('\n');
}

Link *initLink()
{
	Link *head = (Link *)malloc(sizeof(Link));
	if(head != NULL)
	{
		head->data = 0;
		head->next = NULL;
		return head;
	}
	return NULL;
}

Link *headInsert(Link *head, int num)
{
	Link *new = (Link *)malloc(sizeof(Link));
	if(new != NULL)
	{
		new->data = num;
		new->next = head->next;
		head->next = new;
		head->data ++;
		return head;
	}
	return NULL;
}

int main()
{
	int i;
	Link *head = initLink();
	if(head == NULL)
	{
		exit(0);
	}
	for(i=1;i<6;i++)
	{
		head = headInsert(head, i);
	}
	printfLink(head);
	printf("hava %d nodes\n", head->data);
	
	return 0;
}

尾插法插入新节点形成链表

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

typedef struct Node
{
	int data;
	struct Node *next;
}Link;

Link printfLink(Link *head)
{
	Link *point = head->next;
	while(point != NULL)
	{
		printf("%d\t", point->data);
		point = point->next;
	}
	putchar('\n');
}

Link *initLink()
{
	Link *head = (Link *)malloc(sizeof(Link));
	if(head != NULL)
	{
		head->data = 0;
		head->next = NULL;
		return head;
	}
	return NULL;
}

Link *tailInsert(Link *head, int num)
{
	Link *point = head;
	Link *new = (Link *)malloc(sizeof(Link));
	if(new != NULL)
	{
		new->data = num;
		while(point->next != NULL)
		{
			point = point->next;
		}
		point->next = new;
		head->data ++;
		return head;
	}
	return NULL;
}

int main()
{
	int i;
	Link *head = initLink();
	if(head == NULL)
	{
		exit(0);
	}
	
	for(i=1;i<6;i++)
	{
		head = tailInsert(head, i);
	}

	printfLink(head);
	printf("hava %d nodes\n", head->data);

	return 0;
}

指定节点之前插入新节点

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

typedef struct Node
{
	int data;
	struct Node *next;
}Link;

Link *addNodeToLink(Link *head, Link *newNode, int pos);

Link printfLink(Link *head)
{
	Link *point = head->next;
	while(point != NULL)
	{
		printf("%d\t", point->data);
		point = point->next;
	}
	putchar('\n');
}

Link *initLink()
{
	Link *head = (Link *)malloc(sizeof(Link));
	if(head != NULL)
	{
		head->data = 0;
		head->next = NULL;
		return head;
	}
	return NULL;
}

Link *tailInsert(Link *head, int num)
{
	Link *point = head;
	Link *new = (Link *)malloc(sizeof(Link));
	if(new != NULL)
	{
		new->data = num;
		while(point->next != NULL)
		{
			point = point->next;
		}
		point->next = new;
		head->data ++;
		return head;
	}
	return NULL;
}

int main()
{
	int i;
	int pos;
	Link *head = initLink();
	Link newNode = {
		.data = 100,
		.next = NULL
	};

	if(head == NULL)
	{
		exit(0);
	}
	
	for(i=1;i<6;i++)
	{
		head = tailInsert(head, i);
	}

	printfLink(head);
	printf("hava %d nodes\n", head->data);

	printf("add node before:");
	scanf("%d", &pos);
	head = addNodeToLink(head, &newNode, pos);
	printfLink(head);

	return 0;
}

Link *addNodeToLink(Link *head, Link *newNode, int pos)
{
	Link *point = head->next;
	Link *tmp = head;

	while(point != NULL)
	{
		if(point->data == pos)
		{
			newNode->next = point;
			tmp->next = newNode;
			return head;
		}
		tmp = point;
		point = point->next;
	}
	printf("haven't find data\n");
	return head;
}

指定节点之后插入新节点

改动部分

Link *addNodeToLink(Link *head, Link *newNode, int pos)
{
        Link *point = head->next;
        while(point != NULL)
        {
                if(point->data == pos)
                {
                        newNode->next = point->next;;
                        point->next = newNode;
                        return head;
                }
                point = point->next;
        }
        printf("haven't find data\n");
        return head;
}

删除指定数据域的节点

改动部分

Link *delNode(Link *head, int pos)
{
        Link *point = head->next;
        Link *tmp = head;

        while(point != NULL)
        {
                if(point->data == pos)
                {
                        tmp->next = point->next;
                        free(point);
                        return head;
                }
                tmp = point;
                point = point->next;
        }
        printf("haven't find data\n");
        return head;
}

删除整条链表

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

typedef struct Node
{
	int data;
	struct Node *next;
}Link;

Link *delLink(Link *head);

Link printfLink(Link *head)
{
	Link *point = head->next;
	while(point != NULL)
	{
		printf("%d\t", point->data);
		point = point->next;
	}
	putchar('\n');
}

Link *initLink()
{
	Link *head = (Link *)malloc(sizeof(Link));
	if(head != NULL)
	{
		head->data = 0;
		head->next = NULL;
		return head;
	}
	return NULL;
}

Link *tailInsert(Link *head, int num)
{
	Link *point = head;
	Link *new = (Link *)malloc(sizeof(Link));
	if(new != NULL)
	{
		new->data = num;
		while(point->next != NULL)
		{
			point = point->next;
		}
		point->next = new;
		head->data ++;
		return head;
	}
	return NULL;
}

int main()
{
	int i;
	int pos;
	Link *head = initLink();

	if(head == NULL)
	{
		exit(0);
	}
	
	for(i=1;i<6;i++)
	{
		head = tailInsert(head, i);
	}

	printfLink(head);
	printf("hava %d nodes\n", head->data);

	head = delLink(head);
	if(head == NULL)
	{
		printf("done\n");
	}

	return 0;
}

Link *delLink(Link *head)
{
	Link *tmp = NULL;

	while(head != NULL)
	{
		tmp = head;
		head = head->next;
		free(tmp);
		head = head->next;
	}
	return head;	
}