新しいチェーンテーブルはどのようにエラーを修正するか分かりませんか?

#include <stdio.h>
#include <stdlib.h>
struct node;
typedef struct node *Ptrtonode;//   p   struct node   
typedef Ptrtonode list;//list   ptrtonode     ，           
typedef Ptrtonode position;//               position          
list makelist（list L）;//       ，     list   makelist      ，     list
int isempty(list L);//        ，       true
int islast(position P,list L);//P          ，       position
position find (int x,list L);// L       x
void delete(int x,list L); 
void insert(int x,list L,position P);//P     ， x      L P      x
position findprevious(int x,list L); 
position header(list L);//       
position first(list L);//  
position advance(position P);//  
int retrieve(position P);//retrieve      ，  ，    
void printlist(list L); 
struct node{
  int data;
  position next;
};

void main(){
  list L;
  int n;
  L = makelist(list L); 
  printf("0 represent the element you want to look for in the list
");
  printf("1 represent the element you want to delete in the list
");
  printf("2 represent the element you want to insert in the list
");
 // scanf("%d",&n);
    while (n == 0 || n == 1|| n == 2){ 
    prinf("please input choose:
");
       scanf("%d",&n);
      switch(n){
        case '0':
           printf("please input element you want to look for:
");
                   int c;
             position P;
               scanf("%d",&c);
                P= find(c,L);
                printf("%s",P);
        case '1':
          printf("please input element you want to delete:
");
             int c;
            scanf("%d",&c);
          delete(c,L);
       case '2':
          printf("please input element you want to insert:
");
            int c;

            position P;
             scanf("%d,%s",&c,P);
            insert(c,L,P);
       default:
         return "choosing error";
      }
    }
}

void printlist(list L){
  position P;
  P = header(L);
  printf("the list is :
");
  if(P != NULL)
  do {
    printf("%d--",P -> data);
    p = P -> next;
  }while(P != NULL);
}

list makelist(list L){
   position P;
   P =L;
   P -> next = NULL;
   return P;
}

int isempty(list L){//return true if empty
  return L-> next == NULL;
}

int islast(position P,list L){//ruturn true if P is the last position in list L.parametre(  ，  ) L is unused in this implementation（  ，  ）
     return P -> next == NULL;//judge if the list is last ,if the list is null ,the return's value is true(1)
}

position find (int x,list L){//look for the present node x
   position P;
   p = L -> next;
   while(P != NULL && P -> data != x)
        P = P -> next;
    return P;
}

void delete (int x,list L){
  position P,tmpcell;
     p = findprevious(x,L);
    if(!islast(P,L)){
      tmpcell = P -> next;
      p -> next = tmpcell -> next;
      free(tmpcell);

     printlist(L);
     }
    else
    printf("the list is null
");
}

position findprevious(x,L){//look for the next node  x
  position P;
  P = L;
  while(P -> next != NULL && P -> next -> data != x)
      P = P -> next;
    return P;
}

void insert(int x,list L,position P){
  position tmpcell;
  tmpcell = malloc(sizeof(struct node));
    if(tmp == NULL)
     printf("out of space");
     tmpcell -> data = x;
     tmpcell -> next = P -> next;
     P -> next = tmpcell;
     print(L);
}