c++对对象的未定义引用

我正在做一个简单的c++项目来实现堆类并使用它的函数。我已经写出了大部分代码，当我去尝试一些函数时，当我试图编译时，控制台会告诉我有未引用的符号。代码如下:

Heap.h:

#ifndef HEAP_H
#define HEAP_H


template<typename T>
class Heap {
  T arr[100];
  int heapSize;
  //int parent(int);//returnts the index of the parent
  int leftChild(int);//returns the index of the left child
  int rightChild(int);//returns the index of the right child
  void heapify(T*,int);//made to build the heap;
  void buildHeap();//constructs the heap
public:
  Heap();//default constructor
  Heap(T[], int);//custom constructer accepts an array of type T and size
  ~Heap();//destructor
  void insert(T);//insert a node into the array
 // void heapSort(T*);
  T extractMax (); //return root value and remove it from heap
  T maximum();//return the maximum
  void printHeap();//print the values of the heap

};


#endif

Heap.cpp:

#include "Heap.h"
#include <iostream>

template<typename T>
Heap<T>::Heap() { heapSize = 0; }
template<typename T>
Heap<T>::Heap(T a[], int size) {//accepts an array of Type T
  for(int i =0; i < size; i++)
    arr[i] = a[i];
  heapSize = size;
  buildHeap();
}
template<typename T>
Heap<T>::~Heap() { }

template<typename T>
int Heap<T>::leftChild(int i) { return ((i*2) + 1); } //the left child is given by index*2 +1 


template<typename T>
int Heap<T>::rightChild(int i) { return ((i*2) + 2); } //the right child is given by index*2 +2 

template<typename T>
void Heap<T>::heapify(T* a, int i )
{
  int left, right, largest;
  T temp;
  left = leftChild(i);//get the index for the left child
  right = rightChild(i);//get the index for the right child

  if((left <= heapSize) && a[left] > a[i])//check which index has the largest value and store it
    //also checks if the  index is within the heap size
    largest = left;
  else
    largest = i;
  if((right <= heapSize) && a[right] > a[largest])//check if right child is larger
    largest = right;

  if(largest != i)//swap the values of the child is larger than parent
  {
    temp = a[i];
    a[i] = a[largest];
    a[largest] = temp;
    heapify(a, largest);
  }

}
template<typename T>
void Heap<T>::buildHeap()
{
  int hSize = heapSize;//takes the size of the heap
  for(int i = ((hSize/2)-1); i >= 0 ; i--)//loops through every node to make sure they are sorted
    heapify(arr, i);
}

template<typename T>
T Heap<T>::maximum() { return arr[0]; } //return the first element or root element;
template<typename T>
T Heap<T>::extractMax() //removes the root element and returns it
{
  T max = arr[0];
  T* temp = new T[heapSize-1];//create a temp array
  for(int i = 0; i < heapSize; i++)//store all old vals to temp arr except for first element;
    temp[i] = arr[i+1];
  arr = temp;//set arr to temp array
  heapSize--;//decerease heapsize
  buildHeap(); //rebuild heap
  return max; //return root value;
}

template<typename T>
void Heap<T>::insert(T add) //add is the new element for the heap
{
  arr[heapSize] = add;//add the new element to the end of the arr
  heapSize++;//increase heapsize
  buildHeap(arr, heapSize);//call buildHeap to rebuild and resort the heap with the new element

}

template<typename T>
void Heap<T>::printHeap()
{
  for(int i =0; i < heapSize; i++)
    std::cout<<arr[i];
}

Main.cpp:

#include "Heap.h"
#include <iostream>


using namespace std;


int main() 
{

  int arr[] = {6,7,9,10,2,4,5};
  Heap<int> heap(arr, 7);
  heap.printHeap();

 return 0; 
}

我的makefile。

all: heapmake


heapmake: Main.o Heap.o
    g++  Main.o Heap.o -o heapmake
Main.o:Main.cpp
    g++ -c Main.cpp
Heap.o:Heap.cpp
    g++ -c Heap.cpp
clean:
    rm *o heapmake

我怀疑我没有正确地将文件链接在一起，但我想我会发布所有的代码，以防万一。