title: Regular expression for decimal number up to 2 precision and characters
body: <p>I am new to regular expression and I am trying to form a regular expression for below scenarios having combination of letters and decimal number upto 2 precision:</p>
  
  <pre><code>GBP 23.44   -&gt; Valid
  
  23.44       -&gt; Valid
  
  23          -&gt; Valid
  
  23 GBP      -&gt; Valid
  
  234.44 GBP  -&gt; Valid
  
  234.44      -&gt; Valid
  
  23.334 GBP  -&gt; Invalid
  
  234.443 GBP -&gt; Invalid
  
  234&amp; GBP    -&gt; Invalid  
  </code></pre>
  
  <p>Moreover no other characters should be allowed other than A-Z and a-z and Number with 2 precisions.</p>
  
  <p><strong>My attempt</strong>:</p>
  
  <p>I tried <code>^[Aa-Zz][0-9]+(\\.[0-9]{1,2})?$</code>, but its not working as per the expression numbers always needed to be followed after characters like <code>234.44 GBP</code> is failing to match.</p>
  
  <p>I am not able to form exact expression which satisfy all the scenarios. Please help.</p>