// ブラウザ情報の取得 START ================================
var UA =navigator.userAgent;
var macIE = UA.indexOf("msie") > -1 && (UA.indexOf("mac") > -1);
var safari = UA.indexOf("safari") > -1;
// ================================== ブラウザ情報の取得 END
// EVENT SET ========================================================
function addListener(elem, eventType, func, cap) {
    if(elem.addEventListener) {
        elem.addEventListener(eventType, func, cap);
    } else if(elem.attachEvent) {
        elem.attachEvent('on' + eventType, func);
    } else {
        alert('ご利用のブラウザーはアルファメニューをサポートしてません。');
        return false;
    }
}
function setListeners(e) {
	var i;
	var baseNode = document.getElementById("pb");
	if( document.all ){
		var nodeLength = baseNode.childNodes.length;
	}
	else{
		var nodeLength = ( baseNode.childNodes.length - 1 )/2;
	}
	if( nodeLength >= 3 ){
		for( i = 0; i < nodeLength; i++ ){
			if( document.all ){
				baseNode.childNodes[i].style.display = "none";
			}
			else{
				baseNode.childNodes[(i*2)+1].style.display = "none";
			}
		}
		var ii;
		var randomList = new Array();
		for( ii = 0; ii < nodeLength; ii++ ){
			randomList.push( ii );
		}
		var i = 0;
		while( i < 3 ){
			var ary = nodeLength - i;
			randomNum = Math.floor( Math.random() * ary );
			targetNum = randomList[randomNum];
			if( document.all ){
				baseNode.childNodes[targetNum].style.display = "block";
			}
			else{
				baseNode.childNodes[( targetNum * 2 ) + 1].style.display = "block";
			}
			randomList.splice( randomNum,1 );
			i++;
		}
	}
	else{
		for( i = 0; i < nodeLength; i++ ){
			if( document.all ){
				baseNode.childNodes[i].style.display = "block";
			}
			else{
				baseNode.childNodes[(i*2)+1].style.display = "block";
			}
		}
	}
	return;
}
addListener(window, 'load', setListeners, false);