#include <iostream>
#include <cstring>
using namespace std;

template <typename T> double average(T* n,int size)
{
    double sum = 0;
    for (int i = 0; i < size; i++) sum += *(n+i);
    return sum/size;
}

int main()
{
    int x[5] = {2,4,7,8,9};
    double y[3] = {7.8,9.1,0.9};
    unsigned short z[4] = {2,4,6,8};
    const char cstring[] = "ABCD";
    cout << average(x,5) << endl;
    cout << average(y,3) << endl;
    cout << average(z,4) << endl;
    cout << average(cstring,strlen(cstring)) << endl;
}