title: Regular Expression to validate the Country code of mobile number in javascript
body: <p>I need a regular expression that will  test the input</p>
  
  <ol>
  <li>Should start with only one + symbol or optional ( + should not come in between )</li>
  <li>should not contain alphabets and any other special character</li>
  <li>Should not contain consecutive + symbols </li>
  </ol>
  
  <p>eg</p>
  
  <ul>
  <li>+91 (valid)</li>
  <li>91 (valid)</li>
  <li>++91 (invalid)</li>
  <li>+9+1 (invalid)</li>
  <li>91+ (invalid)</li>
  <li>+91&amp;*&amp; (invalid)</li>
  </ul>
  
  <p>Need your inputs on this . Thanks </p>