重新开始数据结构（第二天）链表各函数实现

//链表初始化函数 
node *List_Init(int n)
{
 
 node *head = NULL, *pr;
 while(n--)
 { 
  node *p = new node;
  int data_;
  cin>>data_;
  p->next = NULL;
  p->data = data_;
  if(head == NULL)
   head = p;
  else
   pr->next = p;
  pr = p; 
 }
 return head;
}

//链表打印函数
void List_Print(node *head)
{
 while(head->next != NULL)
 {
  cout<<head->data<<" ";
  head = head->next;   
 }
 cout<<head->data;
 cout<<endl;
 return;
} 

//销毁线性表
void List_Destory(node *head)
{
 head = NULL;
 return; 
} 

//清空线性表
void List_clear(node *head)
{
 while(head->next != NULL)
 {
  head->data = 0;
  head = head->next; 
 }
 head->data = 0;
 return; 
}

//判断线性表是否为空
bool If_List_Empty(node *head)
{
 if(head = NULL)
  return true;
 else 
  return false; 
}

//判断线性表长度 
void List_Size(node *head)
{
 int n = 0;
 while(head->next != NULL)
  n++;
 n++;
 cout<<n;
}

//提取线性表特定节点的数据
int *List_Retrival(node* head, int n)
{
 n -= 1;
 while(n--)
  head = head->next;
 int *p_data = &(head->data);
  return p_data; 
}

//返回线性表指定数据元素的位置
int List_Locate(node *head, int num)
{
 int n = 1;
 while(head->data != num)
 {
  n++;
  head = head->next; 
 }
 
 return n; 
}

//返回指定位置的直接前驱数据
int List_Prior(node *head, int n)
{ 
 n -= 2;
 while(n--)
  head = head->next;
 return head->data;  
} 

//在线性表指定位置插入元素
node *List_Insert(node *head, int n)
{
 node *pr = head;
 n -= 2;
 while(n--)
  head = head->next;
 node *p = new node;
 int data_;
 cout<<"请输入节点数据:"; 
 cin>>data_;
 p->data = data_;
 p->next = head->next;
 head->next = p;
 return pr; 
}

//删除线性表指定位置的元素
node *List_Delete(node *head, int n)
{
 n -= 2;
 node *pr = head;
 while(n--)
  head = head->next;
 head->next = head->next->next;
 return pr;
}

//测试函数
#include <iostream>
using namespace std;
struct node
{
 int data;
 node *next = NULL; 
};
int main()
{
 int n;
 cout<<"请输入节点数："; 
 cin>>n;
 cout<<"测试链表初始化函数：";
 node *head = List_Init(n);
 cout<<"测试链表打印函数：";
 List_Print(head);
 cout<<"返回直接前驱函数测试：";
 int m;
 cin>>m;
 cout<<"其直接前驱为："<<List_Prior(head, m)<<endl;
 cout<<"测试在指定位置插入元素函数：";
 int o;
 cin>>o;
 List_Print(List_Insert(head, o));
 cout<<"测试在指定位置删除元素函数：";
 int p;
 cin>>p;
 List_Print(List_Delete(head, p));
 return 0; 
} 

谢谢观看，错误之处恳求各位指正。