title: What does this regular expression mean: \\d{3}-\\d{4}.*
body: <p>Please notice the spaces in the regx! Anyway thank everybody who try to contribute. With spaces, it is really challenging I guess.</p>
  
  <p>I saw the current code has the following:</p>
  
  <pre><code>Perl5Compiler compiler = new Perl5Compiler();
  Perl5Matcher matcher = new Perl5Matcher();
  Pattern pattern = compiler.compile("\\ d{ 3 } -\\d{4}.* "); // pattern for string starting with " 00 0 - 00 0 0 "   
  
  if (matcher.matches(Num, pattern)) {  
      return true;  
  }  
  </code></pre>
  
  <p>However, I don't feel right that the <code>"\\ d{ 3 } -\\d{4}.* "</code> will match <code>" 00 0 - 00 0 0 "</code>. Anyone know what the real meaning of this regular expression? Or from another perspective, what's the correct regex for " 00 0 - 00 0 0 "?</p>