64-bit Hash Challenge with Prize

[jfcg...@gmail.com]

Hi,

Txt2int is a 64-bit hash (https://github.com/jfcg/sixb) of which I could not identify any collisions yet.

I am really curious about the nature of its collisions so I am offering the following rewards:

- $50 for a first collision
- $100 for "minimum sum of colliding input lengths" (with rigorous proof)

Thanks..

[Aleksei Udovenko]

Hi,

str: CBFA]EC[rKAFZ@EOD hash: 0x1111111111111111
str: JD^KACOIKJLG::CDB hash: 0x1111111111111111

Best Regards,
Aleksei

[Serhat Sevki Dincer]

Thanks Mr. Udovenko :D confirmed.

I have some questions:
- We have tried 5 x 2^37 consecutive small (<6 bytes) utf8-ish string
inputs but no collision yielded. How did it survive that many inputs?
- Is this a bijection for small strings? if so, why?
- How many steps did it take to break it? Could you share your code if
you dont mind?
- what do you think about "minimum sum of colliding input lengths"?
what could it be?
- Do you accept Ether or Zcash :)

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