How to use this function to test if memory is aligned?

I'm a simd beginner, I've read this article about the topic (since I'm using a AVX2-compatible machine).

Now, I've read in this question to check if your pointer is aligned.

I'm testing it with this toy example main.cpp:

#include <iostream>
#include <immintrin.h>

#define is_aligned(POINTER, BYTE_COUNT) \
    (((uintptr_t)(const void *)(POINTER)) % (BYTE_COUNT) == 0)


int main()
{
  float a[8];
  for(int i=0; i<8; i++){
    a[i]=i;
  }
  __m256 evens = _mm256_set_ps(2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 14.0, 16.0);
  std::cout<<is_aligned(a, 16)<<" "<<is_aligned(&evens, 16)<<std::endl;   
  std::cout<<is_aligned(a, 32)<<" "<<is_aligned(&evens, 32)<<std::endl;   

}

And compile it with icpc -std=c++11 -o main main.cpp.

The resulting printing is:

1 1
1 1

However, if I add thhese 3 lines before the 4 prints:

for(int i=0; i<8; i++)
  std::cout<<a[i]<<" ";
std::cout<<std::endl;

This is the result:

0 1 2 3 4 5 6 7 
1 1
0 1

In particular, I don't understand that last 0. Why is it different from the last printing? What am I missing?