title: Fast way to load all alphabetic characters to a hashmap
body: <p>For example I have this Hashmap: </p>
  
  <pre><code>Map&lt;String,Integer&gt; map = new HashMap&lt;&gt;();
  </code></pre>
  
  <p>Instead of doing <code>map.put("A",0)</code>, <code>map.put("B",0)</code>... until <code>map.put("C",0)</code>, is there any way we can make it fast? </p>