Receiving "x cannot appear in constant-expression" and makefile

Question

I'm using a templatized class with data member int arr[], and my templatized value is a size_t to allow me to create an array of variable size. When I try to create an object of my class, I receive an error stating "Error: n1 cannot appear in constant-expression". I believe this is due to the array size being allocated at run-time, but was under the impression that the templatization would resolve this.

My interface and constructor follow, with my object instantiation after:

#include "cstdlib"

template<size_t arrSize>
class Sortable_list{

using namespace std;

private:

int myArray [arrSize];
void swap(int* x, int* y); //Swapping auxiliary
int li_partition(int arr[], int low, int high); //Last index partition     auxiliary
int rand_partition(int arr[], int low, int high); //Random index     partition auxiliary
void merge(int arr[], int l, int m, int n); //Mergesort auxiliary

public:

Sortable_list();
int size();
void clear();
void ip_insertion();
void ip_quicksort(int arr[], int low, int high);
void mergesort(int arr[], int a, int b);
void rand_quicksort(int arr[], int low, int high);
void display();

~Sortable_list();
Sortable_list(const Sortable_list<arrSize> &copy);
Sortable_list<arrSize> operator =(const Sortable_list<arrSize> &copy);
};

template<size_t arrSize>
Sortable_list<arrSize>::Sortable_list<arrSize>()
{
//seed the random number generator
srand(time(0));

for (int i = 0; i < arrSize - 1; i++)
{
    //Gives each index a random value bounded between 0 (inc) and 1000 (non-inc)
    myArray[i] = rand() % 1000;
}
}

main.cpp:

#include "Sortable_list.h"
#include "cstdlib"

using namespace std;

int main()
{
    size_t n1 = 100;
    size_t n2 = 1000;
    size_t n3 = 10000;
    size_t n4 = 100000;
    size_t n5 = 1000000;
    Sortable_list<n1>() l1;
    Sortable_list<n2>() l2;
    Sortable_list<n3>() l3;
    Sortable_list<n4>() l4;
    Sortable_list<n5>() l5;
}

Further, I need to create 2 executable files, namely PA3-1 and PA3-2, to run my code.

My current makefile follows:

all: Sortable_list
Sortable_list: removal main.o
    g++ -o Sortable_list main.o
main.o: main.cpp
    g++ -c -g main.cpp
removal:
    rm -f *.o

This implementation returns the error:

"Sortable_list.h: In instantiation of ‘void Sortable_list::clear() [with long unsigned int arrSize = 1000ul]’: Sortable_list.h:257:11: required from ‘Sortable_list::~Sortable_list() [with long unsigned int arrSize = >1000ul]’ main.cpp:9:25: required from here Sortable_list.h:54:5: warning: deleting array ‘((Sortable_list<1000ul>*)this)->Sortable_list<1000ul>::myArray’ [enabled by >default]"