function checkLanguage(navLanguage) {
	if(navLanguage.indexOf("ja") < 0) {
		window.location.href = "./index_en.html"
	} else {
		void(0);
	}
}

if(navigator.language) {
	var i = navigator.language;
	checkLanguage(i);
} else if(navigator.userLanguage) {
	var i = navigator.userLanguage;
	checkLanguage(i);
} else {
	void(0);
}