title: Given an input string of random letters find letters that make up numbers in Java
body: <p>I am looking to write a program where I am given a string containing jumbled letters from several concatenated words. Each word is a number from zero to nine. Each number may be in the string multiple times. I need to write a program that returns integers corresponding to the letters in the string. </p>
  
  <p>For example:</p>
  
  <p>input: reuonnoinfe
  output: 149</p>
  
  <p>explanation: the given string has one, four and nine</p>
  
  <p>what I have tried so far is:</p>
  
  <pre><code>    public static int strConv(String str) {
      HashMap&lt;Character, Integer&gt; charCount = new HashMap&lt;&gt;();
      for (char c : s.toCharArray()) {
          Integer count = charCount.get(c);
          if (count == null) count = 0;
          map.put(c, ++count);
      }
  }
  </code></pre>
  
  <p>Note: If there are enough characters for multiple of the same numbers, I am expected to simply print the same number over again (ie. input: ooonneeto would be 112)</p>
  
  <p>I am new to java so unsure how to proceed. I am adding all characters I see to a map. Not sure what the next step would be? How can I check if the characters I have in my map correlate to any numbers between 0 and 9? </p>