—— 请按键盘 空白键 开始游戏 ——

True happiness arises, in the first place, from the enjoyment of one's self, and in the next, from the friendship and conversation of a few select companions.
在数学的世界里,每个问题都会引出另一个问题,创造出一个连接所有科学领域的无尽知识网络。