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	var init = function() {

		var pr = document.getElementById('post-revisions'),

		inputs = pr ? pr.getElementsByTagName('input') : [];

		pr.onclick = function() {

			var i, checkCount = 0, side;

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				checkCount += inputs[i].checked ? 1 : 0;

				side = inputs[i].getAttribute('name');

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				! ( inputs[i+1] && inputs[i+1].checked && 'right' == inputs[i+1].getAttribute('name') ) )

					inputs[i].style.visibility = 'hidden';

				else if ( 'left' == side || 'right' == side )

					inputs[i].style.visibility = 'visible';

			}

		}

		pr.onclick();

	}

	if ( w && w.addEventListener )

		w.addEventListener('load', init, false);

	else if ( w && w.attachEvent )

		w.attachEvent('onload', init);

})(window);