title: unordered_map Vs map Vs array - Memory analysis
body: <p>As the title says, I would want to know the memory differences between <code>unordered_map</code>, <code>map</code>, and <code>array</code>.</p>
  
  <p>Example:</p>
  
  <pre><code>unordered_map &lt;long long , int&gt; a;
  map &lt;long long , int&gt; b;
  long long c[1000000];
  </code></pre>
  
  <p><code>a</code> and <code>b</code> have 1000000 stored elements. </p>
  
  <p>I want to keep it as simple as possible. I searched on the internet and I didn't find a proper answer. I found that <code>map</code> and <code>unordered_map</code> use more memory than an <code>array</code>, but I don't know how to approach it. </p>
  
  <p>EDIT: How to approach the memory differences, like if I store exact the same 2 elements, what are the memory differences.</p>