Preparation code

<script>
  var high = Math.pow(2,50);
  var rx = /^10*$/;
  function isPow2rx(x){return (rx.test(x.toString(2)));}
  function isPow2bi(x){return !(x&x-1) && x>0}
</script>
    

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for(var i = 0; i < 9999; i++){
	isPow2rx(i);
}

for(var i = high - 10000; i <= high; i++){
	isPow2bi(i);
}

for(var i = high - 10000; i <= high; i++){
	isPow2rx(i);
}

for(var i = 0; i < 9999; i++){
	isPow2bi(i);
}

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL.

• Revision 1: published @thurmda on 2011-6-21
• Revision 2: published Calvin Metcalf on 2013-4-27
• Revision 3: published Calvin on 2013-4-27
• Revision 4: published on 2015-5-15

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