イメージ： https://www.google.com/search?client=firefox-b-d&biw=1362&bih=724&tbm=isch&sa=1&ei=p1l-XYizOYOUr7wPqd6TgAY&q=%E5%BE%B3%E5%B7%9D%E6%85%B6%E5%96%9C&oq=%E5%BE%B3%E5%B7%9D&gs_l=img.1.1.0l10.11337.24843..26797...14.0..0.82.1887.28......0....1..gws-wiz-img.....0..0i4j0i4i24.rSE3NbJ5NWw
思考の /dev/null
