D:\data structure\homework(c)\main.cpp|183|error: base operand of '->' has non-pointer type 'NODE<int>'|

This error message suggests that you are trying to use the "->" operator on a variable that is not a pointer. The "->" operator is used to access a member of a pointed-to object.

For example, if you have a pointer to a struct called "person":

struct person {
   string name;
   int age;
};

person* ptr_person = new person;

You can access the "name" member using "->":

ptr_person->name = "John";

However, if you try to use "->" on a non-pointer variable, you will get the error you described:

NODE<int> myNode;
myNode->data = 5; // Error: myNode is not a pointer

To fix this error, you should use the "." operator instead of "->" when accessing members of non-pointer objects:

NODE<int> myNode;
myNode.data = 5; // This is correct