链表中的未知语法错误排序程序

Question

分配是为链表创建排序功能。能够编码，但我得到了大量未知的语法错误。我怀疑它可能是Visual Studio（教授要求它），但我想看看你们的想法。大多数错误都存在于头文件（SortedList.h）中，但是我的教授提供了这段代码，所以它没有意义，它不起作用。

EDIT:
Errors include:
-Missing type specifier - int assumed Note: C++ does not support default int 
(sortedlist.h Line:4)
-Syntax error missing ; before identifier ItemType (sortedlist.h Line:4)
-'string' ambiguous symbol (sortedlistprogram.cpp Line:12)
-Syntax error: Identifier 'itemType' (Sortedlist.h Line 14)
-Unexpected token(s) proceeding ';' (sortedlist.h Line 34)



//SortedList.h (header file)
#include <string>
const int MAX_ITEMS = 20;
typedef string ItemType;
class SortedList
{
public:
  SortedList();
  // Constructor
  // Post: Empty list is created.

  // Action responsibilities
  void Insert(ItemType item);
  // Pre:  The list is not full; 
  // Post: item is in the list; list is stored in
  //       increasing order.
  void PrintList();
  // Post: If the list is not empty, the elements are
  //       printed on the screen in increasing order; 
  //       otherwise "The list is empty" is
  //       printed on the screen.

  // Knowledge responsibilities
  int GetLength();
  // Post: return value is the number of items in the list.
  bool IsEmpty();
  // Post: returns true if list is empty; false otherwise.
  bool IsFull();
  // Post: returns true if there is no more room in the
  //       list; false otherwise.
private:
   int length;
   ItemType values[MAX_ITEMS];
};
//SortedList.CPP
#include "sortedList.h"
#include <iostream>
#include<string>
#include<algorithm>
using namespace std;
SortedList::SortedList()
{
   length = 0;
}
bool SortedList::IsEmpty()
//Function to check if empty
{
  if (values->empty())
       return true;
    return false;
}
 bool SortedList::IsFull()
 //Function to check if full
{
    if (length == MAX_ITEMS)
        return true;
     return false;
 }
void SortedList::Insert(ItemType item)
//Insert function for SortedList
{
    if (!IsFull())
    {
    values[length] = item;
    ++length;
    sort(values, values + length);
   }
}
int SortedList::GetLength()
//Function to return length
{
    return length;
}
void SortedList::PrintList()
//Function to print list
{
    if (IsEmpty())
    {
       cout << "List is empty" << endl;
    }
    else
    {
        for (int index = 0; index < length; ++index)
    {
        cout << values[index] << endl;
    }
    cout << endl << "There are " << GetLength() << " items in the list" << 
   endl;
  }
}
//Driver.CPP
#include "sortedList.h"
#include <fstream>
#include <string>
#include <iostream>
using namespace std;

int main()
{
string value;
SortedList list;
list.PrintList();
ifstream file("word.in");
//calls word.in file
if (file.good())
    //Checks if file is good
{
    while (getline(file, value))
    {
        list.Insert(value);
    }
    file.close();
}
list.PrintList();
//Prints list

return 0;
}