function RandomSelectMyMiniCityImproveType(level) {
	// 都市の拡大を目指すならアクセスの比
	//	Δpop : Δind : Δsec : Δtra : Δenv : Δcom
	// は
	//	 1 : 1/3 : 1/5 : 1/4 : 13/60 : 0
	var	wait = new Array(60, 20, 12, 15, 13, 0);
	var	path = new Array('', 'ind/', 'tra/', 'sec/', 'env/', 'com/');
	var	weightSum;
	var	i;
	var	selected;

	weightSum = 0;
	for (i = 0; i < level; i++) {
		weightSum += wait[i];
	}
	selected = Math.floor(Math.random() * weightSum);

	weightSum = 0;
	for (i = 0; i < level; i++) {
		weightSum += wait[i];
		if (selected < weightSum) {
			selected = path[i];
			break;
		}
	}

	return selected;
}

function ChangeRandomImproveMyMiniCityLink(url, level) {
	var	cityLink = document.getElementsByTagName('a');
	var	i;

	// Safari の乱数の seed は一定なので現在時刻の秒で攪乱する。
	{
		var	tmp = new Date;

		tmp = tmp.getSeconds();
		for (i = 0; i < tmp; i++) {
			Math.random();
		}
	}

	for (i = 0; i < cityLink.length; i++) {
		if (
			cityLink[i].className == 'MyMiniCityRandomImpove'
				&&
			cityLink[i].getAttribute('href') == url
		) {
			cityLink[i].setAttribute(
				'href',
				url + RandomSelectMyMiniCityImproveType(level)
			);
		}
	}
}