链表那点事

（1）：链表之一

//环形链表 

#include <stdio.h>
#include <stdlib.h>
struct student
{
int data;
struct student *next;
};


typedef struct student node;
typedef  node* list;


int main(void)
{
list head,p1,p2;
int i;
head = (list)malloc(sizeof(node));
p1 = head;
p1->data = 1;
for(i=2;i<7;i++)
{
p2 = (list)malloc(sizeof(node));
p2->data = i;
p1->next = p2;
p2->next = NULL;
p1 = p2;

}
p2 = p1;
p1->next = head; //将尾节点指向头 
do
{
printf("p1->data:%d\n",p1->data);

p1 = p1->next;


}while(p1 != p2);

p2 = head;
p1 = head;
do
{


p1 = p1->next;
free(p1);

}while(p2 != p1);-

return 0;

}

（2）：链表之二双向链表

/*
    双向链表: 
data1-->data2-->data3-->NULL
NULL<--data1<--data2<--data3 

*/


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


struct student//存储数据 
{
int data;
struct student *frount;
struct student *back;
};


struct node1//保存头尾节点 
{
struct student *head;
struct student *list;
};


typedef struct student node;
typedef node* list;


typedef struct node1 Node;


void fun(Node * Node1,int len)//Node保存头为节点  len数据长度 
{

int i;
list Frount;
list Back;
list ptr;
list ptr1;
ptr = (list)malloc(sizeof(node));//开辟第一个节点 

if(ptr == NULL)
{
return ;
}
else
{
Frount = ptr;
ptr->frount = NULL;
ptr->back = NULL;
ptr->data = 1;
}

for(i=2;i<len;i++)//用循环开辟空间 
{
ptr1 = (list)malloc(sizeof(node));

ptr1->data = i;
ptr->frount = ptr1;
ptr1->back = ptr;
ptr = ptr1;

}
ptr1->frount = NULL;
Back = ptr1;
Node1->head = Frount;
Node1->list = Back;
}
int main(void)
{
int len;
list Back = NULL;
list Frount = NULL;
Node Node1;

printf("输入数据长度:");
scanf("%d",&len);

fun(&Node1,len);

Back = Node1.list;
Frount = Node1.head;

//输出数据 

while(Back != NULL)//反向输出
{
printf("Back-> back = %d\n",Back->data);
Back = Back->back;
}

while(Frount != NULL)//正向输出
{
printf("Frount -> frount = %d\n",Frount->data);
Frount = Frount->frount;
}


system("pause");
return 0;
}

（3）：链表之三：将连接好的链表逆序

/*
将一条生成好的链表逆向 ：
               
  原链表：data1--->data2--->data3--->data4--->data5--->data6--->NULL 
   
  逆向后的链表: data6-->data5-->data4-->data3-->data2-->data1-->NULL;
                   
*/


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


struct llist
{
int num;
struct llist *next;


};


typedef struct llist node;
typedef node* llink;


int main()
{
llink p1,p2,p3,p4,p5;
llink last,mid;
llink head;
llink next;

//生成节点 p1---p5 
p1 = (llink)malloc(sizeof(node));
p1->num = 1;

p2 = (llink)malloc(sizeof(node));
p2->num = 2;

p3 = (llink)malloc(sizeof(node));
p3->num = 3;

p4 = (llink)malloc(sizeof(node));
p4->num = 4;

p5 = (llink)malloc(sizeof(node));
p5->num = 5;

//将数据连接起来 
p1->next = p2;
p2->next = p3;
p3->next = p4;
p4->next = p5;
p5->next = NULL;

head = p1;
while(head != NULL)//输出原链表的内容 
{
printf("%d\n",head->num);
head = head->next;
}
printf("************\n");

head = p1;//头结点 

mid = NULL;//mid是head前的节点 

while(head != NULL)
{
last = mid; //last是mid前节点 
mid = head;
head = head->next;//下一个节点 
mid->next = last;//mid指向前节点last 
}


//输出节点 
while(mid != NULL)
{
printf("%d\n",mid->num);
next = mid;
mid = mid->next;

free(next);
}


system("pause");
return 0;
}



（4）链表之四：将两条链表合成一条链表:

/*
  将两条链表合成一条链表：
  
  一条链表：data1-->data2-->data3-->data4-->data5-->NULL;
     另一条链表:  temp1-->temp2-->temp3-->temp4-->temp5-->NULL;

合成后的链表:data1-->data2-->data3-->data4-->data5--> temp1-->temp2-->temp3-->temp4-->temp5-->NULL; 
   
*/
#include <stdio.h>
#include <stdlib.h>
struct student
{
int number;
struct student *next;
};


typedef struct student node;
typedef node* list;


int main(void)
{
list head = (list)malloc(sizeof(list));
head->number = 1;

list pointer = (list)malloc(sizeof(list));
pointer->number = 5;

list head1 = head;
list pointer1 = pointer;

list next1;

int i;

for(i=2;i<5;i++)//第一条链表 
{

next1 = (list)malloc(sizeof(list));
next1->number = i;

head1->next = next1;
head1 = next1;
next1 -> next = NULL;

 
}

for(i=6;i<10;i++)//第二条链表 
{
next1 = (list)malloc(sizeof(list));
next1->number = i;
pointer1->next = next1;
pointer1 = next1;
next1->next = NULL;

}

head1->next = pointer;//将两条链表连接起来 

next1 = head;
while(next1 != NULL)
{
printf("next->number: %d\n",next1->number);
next1 = next1->next;
}

next1 = head->next;

while(next1 != NULL)//释放节点 
{
free(head);
head = next1;
next1 = head->next;


}

system("pause");
return 0;
}