Шаблонный класс

#include <iostream>
#include <ctime>
#include <clocale>
template< typename T >
T avg( const T* arr, unsigned int size_arr )
{
    T sum = 0;
    for ( unsigned int i = 0; i < size_arr; ++i )
    sum += arr[ i ];
    return sum / size_arr;
}
int main(void)
{
    setlocale(LC_ALL,"Rus");
    srand(time(0));
    const int length_array = 10;
    int vector[length_array];
    double vectorDouble[length_array];
 
    for (int counter = 0; counter < length_array; counter++)
    {
        vector[counter] = rand() % 100;
        vectorDouble[counter] = vector[counter];
        std::cout << vector[counter] << " ";
    }
 
    std::cout << "\nсреднее арифметическое DOUBLE = " << avg<double>(vectorDouble, length_array) << std::endl;
    std::cout << "\nсреднее арифметическое INT = " 
<< avg<int>(vector, length_array)<< std::endl;
    system("pause");
    return (int)NULL;
}