双向链表

#include<stdio.h>

#include<stdlib.h>

typedef struct list

{

 int data;

 struct list*left;

 struct list*right;

}List;

void insert_list_2nd(List*head,int data);

void insert_list_last(List*head,int data);

void insert_list_order(List*head,int data);

void print_list(List*head);

void delete_list(List*head,int value);



int main()

{ int i;

 List*head=(List*)malloc(sizeof(List)); 

 head->data=-1;

 head->left=head->right=NULL;

// for(i=0;i<10;i++)

  //insert_list_last(head,i);

//  insert_list_2nd(head,i);

 for(i=9;i>=0;i--)

  insert_list_order(head,i);

 print_list(head);

 for(i=0;i<10;i++)

  delete_list(head,i);

 print_list(head);

 

} 



void insert_list_2nd(List*head,int data)

{

 List*newnode=(List*)malloc(sizeof(List));

 newnode->data=data;

 newnode->right=head->right;

 head->right=newnode;

 newnode->left=head;

 if(newnode->right)

 {

  newnode->right->left=newnode;

 }   

}

void insert_list_last(List*head,int data)

{ List*newnode=(List*)malloc(sizeof(List));

 newnode->data=data; 

 while(head->right)

 {

  head=head->right;

 }

 head->right=newnode;

 newnode->left=head;

 newnode->right=NULL;

   

}

void insert_list_order(List*head,int data)

{ List*newnode=(List*)malloc(sizeof(List));

 newnode->data=data; 

 while(head->right && head->right->data<data)

 {

  head=head->right;

 }

 if(head->right==NULL)

 {

  head->right=newnode;

  newnode->left=head;

  newnode->right=NULL;  

 } 

 else

 {

  newnode->right=head->right;

  head->right=newnode;

  newnode->left=head;

  newnode->right->left=newnode; 

 }

}

void print_list(List*head)

{

 while(head)

 {

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

  head=head->right;

 } 

}

void delete_list(List*head,int value)

{

 List *temp;

 while(head->right && head->right->data!=value)

 {

  head=head->right;

 }

 if(head->right==NULL)

 {

  printf("don't have %d\n",value);

  return ;

 } 

 else

 {

  temp=head->right;

  head->right=temp->right;

  if(temp->right) 

  {

   temp->right->left=head;

  }

  free(temp);

 }

  

}