title: HashMaps and operations
body: <p>I have a problem with HashMap.
  I want to put into map:</p>
  
  <pre><code>key - 320, value - 0.1
  key - 321, value - 0.7
  key - 322, value - 0.5
  key - 323, value - 0.6
  </code></pre>
  
  <p>After that I want to sort this map in descending order like this:</p>
  
  <pre><code>key - 321, value - 0.7
  key - 323, value - 0.6
  key - 322, value - 0.5
  key - 320, value - 0.1
  </code></pre>
  
  <p>and after that I want to sort map in ascending order, but only values:</p>
  
  <pre><code>key - 321, value - 0.1
  key - 323, value - 0.5
  key - 322, value - 0.6
  key - 320, value - 0.7
  </code></pre>
  
  <p>This is possible in hashmaps? How I can do this?</p>