title: The posix_memalign() function in c++
body: <p>I have read documentations about <code>posix_memalign()</code>. I still not sure how to deal with this <code>The value of alignment shall be a power of two multiple of sizeof(void *).</code>
  Also, I need some error messages to check that my alignment is successful.</p>
  <p>I need to allocate memories aligned with 64bytes for the following arrays along with error messages for check up.</p>
  <pre><code>int array_dataset [5430][20];
  int X_train [4344][20];
  int Y_train[4344];
  int data_point [20];
  int Y-test [1068];
  int X_test [1068][20]; 
  </code></pre>