—— 请按键盘 空白键 开始游戏 ——

Mathematics is not a careful march down a well-cleared highway, but a journey into a strange wilderness, where the explorers often get lost.
数学不是沿着一条清理得很好的高速公路小心行进,而是进入一个陌生的荒野的旅程,探险者常常会迷路。
The present is the past rolled up for action, and the past is the present unrolled for understanding.
拥有朋友的唯一方式是成为朋友。