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Security# BrainTeaser - 大脑工作室

d*u2007-05-11 07:05

1 楼

You want to send a valuable object to a friend securely.
You have a box which can be fitted with multiple locks,
and you have several locks and their corresponding keys.
However, your friend does not have any keys to your locks,
and if you send a key in an unlocked box,
the key could be copied en route.
How can you send the object securely?

h*r2007-05-11 07:05

2 楼

如果他有自己的 keys 和 lock:
you lock the object in the box, send the box to him. he add a lock and send
back, you open your lock and send back to him, and he open his lock.

【在 d**u 的大作中提到】

: You want to send a valuable object to a friend securely.
: You have a box which can be fitted with multiple locks,
: and you have several locks and their corresponding keys.
: However, your friend does not have any keys to your locks,
: and if you send a key in an unlocked box,
: the key could be copied en route.
: How can you send the object securely?

o*r2007-05-11 07:05

3 楼

脑筋急转弯

send

【在 h**r 的大作中提到】

: 如果他有自己的 keys 和 lock:
: you lock the object in the box, send the box to him. he add a lock and send
: back, you open your lock and send back to him, and he open his lock.

p*e2007-05-11 07:05

4 楼

真费劲

send

【在 h**r 的大作中提到】

: 如果他有自己的 keys 和 lock:
: you lock the object in the box, send the box to him. he add a lock and send
: back, you open your lock and send back to him, and he open his lock.

h*02007-05-11 07:05

5 楼

不行，他的锁来时可能被人调换了。

send

【在 h**r 的大作中提到】

: 如果他有自己的 keys 和 lock:
: you lock the object in the box, send the box to him. he add a lock and send
: back, you open your lock and send back to him, and he open his lock.

i*g2007-05-11 07:05

6 楼

mutiple delivery?
2 keys Ka, Kb , match 2 locks La, Lb respectively. 3 boxes: B1, B2, B3
Ka inside B1 with Lb locked
Kb inside B2 unknocked
Valuable object inside B3 with La locked

【在 d**u 的大作中提到】

i*g2007-05-11 07:05

7 楼

good one though

send

【在 h**r 的大作中提到】

: 如果他有自己的 keys 和 lock:
: you lock the object in the box, send the box to him. he add a lock and send
: back, you open your lock and send back to him, and he open his lock.

f*e2007-05-11 07:05

8 楼

如果这个技巧可以用的话，可以考虑先多把锁锁上了
送过去，朋友把开不了的锁留着，开的了的锁开了，但是一起邮寄回来，
偶拿掉那些没有开的锁，再把能开的锁锁上，再送到朋友那里去

send

【在 h**r 的大作中提到】

: 如果他有自己的 keys 和 lock:
: you lock the object in the box, send the box to him. he add a lock and send
: back, you open your lock and send back to him, and he open his lock.