Duplicate Checker

by Sam Fereday

HTML

<ul class="rcbList" style="list-style:none;margin:0;padding:0;zoom:1;">
  <li class="rcbItem  rcbTemplate"><span>Afghanistan (+93)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Albania (+355)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Algeria (+213)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Andorra (+376)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Angola (+244)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Antarctica (+672)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Argentina (+54)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Armenia (+374)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Aruba (+297)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Ascension Island (+247)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Australia (+61)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Austria (+43)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Azerbaijan (+994)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Bahrain (+973)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Bangladesh (+880)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Belarus (+375)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Belgium (+32)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Belize (+501)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Benin (+229)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Bhutan (+975)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Bolivia (+591)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Bosnia and Herzegovina (+387)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Botswana (+267)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Brazil (+55)</span></li>
  <li class="rcbItem  rcbTemplate"><span>British Indian Ocean Territory (+246)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Brunei Darussalam (+673)</span></li>
  <li class="rcbItem  rcbTemplate"><span>Burkina Faso (+226)</span></li>
  <li class="rcbItem ...

JavaScript

const d = [{
    country: 'Afghanistan',
    dialCode: '+93',
    code: 'AF'
  },
  {
    country: 'Åland Islands',
    dialCode: '+358',
    code: 'AX'
  },
  {
    country: 'Albania',
    dialCode: '+355',
    code: 'AL'
  },
  {
    country: 'Algeria',
    dialCode: '+213',
    code: 'DZ'
  },
  {
    country: 'American Samoa',
    dialCode: '+1684',
    code: 'AS'
  },
  {
    country: 'Andorra',
    dialCode: '+376',
    code: 'AD'
  },
  {
    country: 'Angola',
    dialCode: '+244',
    code: 'AO'
  },
  {
    country: 'Anguilla',
    dialCode: '+1264',
    code: 'AI'
  },
  {
    country: 'Antarctica',
    dialCode: '+672',
    code: 'AQ'
  },
  {
    country: 'Antigua and Barbuda',
    dialCode: '+1268',
    code: 'AG'
  },
  {
    country: 'Argentina',
    dialCode: '+54',
    code: 'AR'
  },
  {
    country: 'Armenia',
    dialCode: '+374',
    code: 'AM'
  },
  {
    country: 'Aruba',
    dialCode: '+297',
    code: 'AW'
  },
  {
    country: 'Australia',
    dialCode: '+61',
    code: 'AU'
  },
  {
    country: 'Austria',
    dialCode: '+43',
    code: 'AT'
  },
  {
    country: 'Azerbaijan',
    dialCode: '+994',
    code: 'AZ'
  },
  {
    country: 'Bahamas',
    dialCode: '+1242',
    code: 'BS'
  },
  {
    country: 'Bahrain',
    dialCode: '+973',
    code: 'BH'
  },
  {
    country: 'Bangladesh',
    dialCode: '+880',
    code: 'BD'
  },
  {
    country: 'Barbados',
    dialCode: '+1246',
    code: 'BB'
  },
  {
    country: 'Belarus',
    dialCode: '+375',
    code: 'BY'
  },
  {
    country: 'Belgium',
    dialCode: '+32',
    code: 'BE'
  },
  {
    country: 'Belize',
    dialCode: '+501',
    code: 'BZ'
  },
  {
    country: 'Benin',
    dialCode: '+229',
    code: 'BJ'
  },
  {
    country: 'Bermuda',
    dialCode: '+1441',
    code: 'BM'
  },
  {
    country: 'Bhutan',
    dialCode: '+975',
    code: 'BT'
  },
  {
    country: 'Bolivia, Plurinational State of bolivia',
    dialCode: '+591',
    code: 'BO'
  },
  {
    country: 'Bosnia and...