C implements chain queues

This paper shares the specific code of C language chain queue for your reference, the specific content is as follows

Source file: if you haven't learned the pointer well, it's hard to understand ^_^. It's a bit messy. I hope it will be helpful to you.

#include<stdio.h>
#include<malloc.h>
#include<stdlib.h>
#include<string.h>
typedef int Elemtype;
#include"LQueue.h"
int main()
{
 Deque head;
 instruction(head);
 return 0;
}
 Header section: 
typedef struct Queue
{
 Elemtype data;
 struct Queue *next;
}LQnode,*LQueue;
 
typedef struct
{
 LQnode *front;
 LQnode *rear;
}Deque;
 
void Init_queue(Deque *head)  // Initialize the + Empty the operation == In this case, to clear means to discard the node after the head node  
{
 LQnode *p=NULL;
 p=(LQueue)malloc(sizeof(LQnode));
 head->front=p;
 head->rear=p; 
 p->next=NULL;
}
 
int Empty_queue(Deque *head)      // Sentenced to empty 
{
 if(head->front->next==head->rear->next)
 return 1;
 return 0;
}
 
int Lenght_queue(Deque arrow)
{
 LQnode *p=NULL;
 int len=0;
 p=arrow.front->next;
 while(p)
 {
 len++;
 p=p->next;
 }
 return len;
}
 
void Enqueue(Deque *arrow,Elemtype e)    // The operation of entrance 
{
 LQueue p=NULL;
 p=(LQueue)malloc(sizeof(LQnode));
 if(!p)
 {
 printf(" No more memory units have been allocated !\n");
 return ;
 }
 p->data=e;
 p->next=NULL;         // When inserting, the first pointer does not need to be moved  
 arrow->rear->next=p;
 arrow->rear=p; 
 return ;
}
 
void Dequeue(Deque *arrow,Elemtype *e)    // The team operation 
{
 LQnode *p=NULL;
 if(Empty_queue(arrow))
 {
 printf(" The current chain queue is empty and cannot be queued !!!\n");
 return ;
 }
 p=arrow->front->next;
 (*e)=p->data;
 arrow->front->next=p->next;
 printf(" The element %d Dequeued !!!\n",*e);
 if(Lenght_queue(*arrow)==0)
 return ;            // When the last 1 So once I get these guys out, arrow->rear I don't know where it's pointing    
 free(p);
 return ;
}
 
int Queue_top(Deque *arrow)  // Returns the header element  
{
 if(Empty_queue(arrow))
 {
 printf(" The current chain queue is empty. The queue header element does not exist !!!\n");
 return 0;
 }
 printf(" The current team header element is: %d\n",arrow->front->next->data);
}
 
void Destroy_queue(Deque *arrow)  // Destruction of chain queues 
{
 LQnode *p=NULL;
 if(Empty_queue(arrow))
 {
 printf(" The current chain queue is empty, no need to complete the destroy operation !!!\n");
 return ;
 }
 while(arrow->front->next)
 {
 p=arrow->front->next;
 arrow->front->next=p->next;
 if(Lenght_queue(*arrow)==0)
  break;   
 free(p);
 }
 printf(" Destruction of success !\n");
 return ;
}
 
void Print_queue(Deque arrow)
{
 LQnode *p=NULL;
 p=arrow.front->next;
 while(p)
 {
 printf("%d ",p->data);
 p=p->next;
 }
 printf("\n");
}
 
void Modify_queue(Deque *arrow,Elemtype index,Elemtype e)  // Modify the function 
{
 int i=0;
 LQnode *p=NULL;
 p=arrow->front->next;
 while(i<index-1)
 {
 p=p->next;
 }
 p->data=e;
 printf(" The modification action has been completed !\n");
}
 
int Insearch_queue(Deque arrow,Elemtype e)      // Lookup function 
{
 LQnode *p=NULL;
 int i=1;
 if(Empty_queue(&arrow))
 {
 printf(" The current chain queue is empty and there are no elements to look up !!!\n");
 return 0;
 }
 p=arrow.front->next;
 while(p!=NULL)
 {
 if(e==p->data)
 {
  return i;
  break;
 }
 i++;
 p=p->next;
 }
 if(p==NULL)
 printf(" The lookup failed. No element exists in the queue !\n");
 return 0;
}
 
void instruction(Deque head)
{
 int n,m,t,a,b,len1,index;
 printf("\t\t1 , queue initialization  \n");
 printf("\t\t2 , new queue elements \n");
 printf("\t\t3 , returns the header element \n");
 printf("\t\t4 Element out of queue  \n");
 printf("\t\t5 , looking for queue elements \n");
 printf("\t\t6 , modify the queue elements \n");
 printf("\t\t7 , destroy the queue   \n");
 printf("\t\t8 , the length of the queue  \n");
 printf("\t\t9 , print queue elements \n");
 printf("\t\t10 , exit the program   \n");
 printf(" Please enter the instructions you need to complete :\n");
 do{
 scanf("%d",&n);
 if(n<1||n>10)
  printf(" Sorry, the instruction number you entered is invalid, please re-enter it !!!\n");
 }while(n<1||n>10);
 switch(n)
 {
 case 1:
  Init_queue(&head);
  printf(" Chain queue initialization has been completed , Please enter the number of elements you want to add !\n");
  scanf("%d",&n);
  while(n--)
  {
  int x;
  scanf("%d",&x);
  Enqueue(&head,x);
  }
  printf(" Complete the team building operation !\n");
  break;
 case 2:
  printf(" Please enter the number of elements you want to add !\n");
  scanf("%d",&n);
  while(n--)
  {
  int x;
  scanf("%d",&x);
  Enqueue(&head,x);
  }
  printf(" Add success !\n");
  break;
 case 3:
  Queue_top(&head);
  break;
 case 4:
  Dequeue(&head,&t);
  break;
 case 5:
  printf(" Please enter the element you are looking for :\n");
  scanf("%d",&m);
  index=Insearch_queue(head,m);
  if(index)
  printf(" The element you are looking for is at the beginning of the queue %d A position !!!\n",index);
  break;
 case 6:
  printf(" Please enter the element queue location that you changed :\n");
  do{
  scanf("%d",&a);
  if(a<1||a>Lenght_queue(head))
   printf(" Sorry, the location of the element you entered is not in the region, please re-enter !!!\n");
  }while(a<1||a>Lenght_queue(head));
  printf(" Please enter the modified value :\n");
  scanf("%d",&b);
  Modify_queue(&head,a,b);
  break;
 case 7:
  Destroy_queue(&head);
  break;
 case 8:
  len1=Lenght_queue(head);
  printf(" The current chain queue length is :%d\n",len1);
  break;
 case 9:
  Print_queue(head);
  break;
 case 10:
  return;
 default:
  instruction(head);
  break;
 }
 instruction(head);
}