🚀 go-pugleaf

I downloaded Eckel's "Thinking in C++" book in PDF format, and I've been
trying to get through the exercises. I'm currently stuck on one of the
problems. I'm pasting everything below:

// Thinking in C++
// Chapter 3 - Exercise 28
// Filename: ch3ex28.cpp
// Assignment: Create a function that takes a pointer to an array of
// double and a value indicating the size of that array. The
// function should print each element in the array. Now
// create an array of double and initialize each element to
// zero, then use your function to print the array. Next use
// reinterpret_cast to cast the starting address of your array
// to an unsigned char*, and set each byte of the array to 1
// (hint: you'll need to use sizeof to calculate the number of
// bytes in a double). Now use your array-printing function
// to print the results. Why do you think each element was
// not set to the value 1.0?

----------------------------------------------------------------------------
------
#include <iostream>
using namespace std;
void printElement(double *ptr, int ptrsize);

void main()
{

 double k[5] = {0, 0, 0, 0, 0};
 printElement(k, sizeof(k)/8);
 unsigned char *startAdd = reinterpret_cast<unsigned char*>(&k);

    for(int i = 0; i < 5; i++)
     {
      startAdd[i] = 1;
     }
     for(i = 0; i < 5; i++)
          cout << startAdd[i] << endl;

}

void printElement(double *ptr, int ptrsize)
{

 for(int i = 0; i < ptrsize; i++)
  cout << ptr[i] << endl;

}
----------------------------------------------------------------------------
------

1) Did I write printElement correctly? Is there another way to tell a
function what the size of the array is?
2) The second for loop in main() prints out null characters. I'm assuming
that the reason that the integer 1 cannot be assigned to *startAdd because
of the differences between unsigned char and double, which not only take up
a different amount of space in memory, but are also of different types. Am I
missing something?
3) Eckel often declares his main() function as an int, but never has a
'return 0;' in any of his programs. My compiler (VC++) spits out an error
when the function doesn't return a value. Is there something wrong with
Eckel's code or my compiler?

Thanks in advance.

-Pawel Mrozik