搞笑
史上最牛诗歌：一个停机问题不可判定的证明
SCOOPING THE LOOP SNOOPER
A proof that the Halting Problem is undecidable
Geoffrey K. Pullum
(School of Philosophy, Psychology and Language Sciences, University of Edinburgh)
No general procedure for bug checks succeeds.
Now, I won’t just assert that, I’ll show where it leads:
I will prove that although you might work till you drop,
you cannot tell if computation will stop.
For imagine we have a procedure called P
that for specified input permits you to see
whether specified source code, with all of its faults,
defines a routine that eventually halts.
Now, I won’t just assert that, I’ll show where it leads:
I will prove that although you might work till you drop,
you cannot tell if computation will stop.
For imagine we have a procedure called P
that for specified input permits you to see
whether specified source code, with all of its faults,
defines a routine that eventually halts.
用布制成的“山寨Klein瓶”
Klein瓶是拓扑学中最神奇的几何体之一，以至于谁家里要是有一个Klein瓶的话我愿意花500块钱把它买下来。不过呢，瞻仰不到Klein瓶也没关系，不要忘记Geek始终是一种富有创造力、喜欢自娱自乐的生物。做不出玻璃瓶子不要紧，做一个“山寨Klein瓶”可谓是出奇的简单。你只需要截取长袖T恤的两条袖子，在其中一个的表面上打一个洞，让另外一个袖子穿过去，然后把对应的口子缝起来即可。然后呢，以后无聊时你就又多了一件事情可以干了：把这个玩意儿拿出来，不停地、没完没了地把“里面”翻出来。
