function tweet() {
	var login  = 'sumachalle'; 
	var apiKey = 'R_ffb1b2d58f3e29f35507bbd9cd61c519'; 
	bitly = 'http://api.bit.ly/shorten' 
	    + '?version=2.0.1&format=json&callback=callback'
	    + '&login=' + login
	    + '&apiKey=' + apiKey + '&longUrl=';
	var script = document.createElement('script');
	script.type = 'text/javascript';
	script.src = bitly + encodeURIComponent(location.href) ;
	document.body.appendChild(script);
}

function callback(bitlyResponse) {
	var ind = document.title.indexOf(' ');
	var title = document.title.slice(0,ind);
	var url = 'http://twitter.com/intent/tweet?text=' 
	    + encodeURIComponent(
	         'すまチャレなう「' + title + '」 #sumachalle ' 
	           + bitlyResponse.results[location.href]['shortUrl']
			   + ' '
	      );
	location.href = url;
	//window.open(url, '_blank');
}