RegExp, match, replace
function sv(v) { var r = new RegExp("&s=[0-9]+"); if(window.location.href.match(r)) window.location.href = window.location.href.replace(r,"&s="+v); else window.location.href = window.location.href+"&s="+v; } var ur = document.getElementById( ...
http://qindex.info/i.php?x=3499

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