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                <div class="container"><div class="row">
  <div class="col-sm-12">
    <h1>Palindrome check</h1>
    <table class="table table-striped">
        <tr><td class="string">123 456 789 09 87 65 43 21</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">012 34 3 21</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">put it up</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">stack cats</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">No ‘x’ in Nixon</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">step on no pets</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">Was it a car or a cat I saw?</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">A man, a plan, a canal - Panama!</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">Doc, note: I dissent. A fast never prevents a fatness. I diet on cod.</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">This is not a palindrome. That's the reason there's a red "x" instead of a green checkmark.</td><td><span class="glyphicon"></span></td></tr>
        <tr><td class="string">T. Eliot, top bard, notes putrid tang emanating, is sad; I'd assign it a name: gnat dirt upset on drab pot toilet.</td><td><span class="glyphicon"></span></td></tr>




                $(document).ready(function() {
  $("tbody tr").each(function() {
    var classes = isPalindrome($(this).children("td.string").text()) ? "glyphicon-ok text-success" : "glyphicon-remove text-danger";

    $(this).find("td .glyphicon").addClass(classes);

function isPalindrome(str) {
    str = str.toLowerCase().replace(/[^a-z0-9]*/g, "");
    var halfLen = Math.floor(str.length / 2);
    var strHalf = str.substring(0, halfLen);
    var strHalfRev = str.substring(str.length-halfLen, str.length);

    return reverse(strHalfRev) == strHalf;

function reverse(s) {
  return s.split('').reverse().join('');