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codecryptanalysis / mccl

modular code cryptanalysis library
MIT License
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MMT DEBUG #18

Open qc20000sj opened 3 months ago

qc20000sj commented 3 months ago

When the MMT program uses this file to search, how can it not search the desired vector.

n864(n-k)432m100poidsmax7.txt

FloydZ commented 2 months ago

@cr-marcstevens I will have look.

FloydZ commented 2 months ago

@qc20000sj : the problem is that the syndrome is zero. The algorithm is constructed in such a way, that it chooses a random intermediate target for the left side of the search tree. Whereas the intermediate target for the right side is set to: iT_left ^ syndrome. If the syndrome is now zero, the two intermediate targets are the same. As a result, the algorithm will find solutions which will sum up to zero. Hence, it will find the zero vector as a solution, which is not correct. I don't have a quick fix for this. So I need think about this a little bit, whats the best solution. As a workaround you could re-randomize your instance.

qc20000sj commented 2 months ago

Thank you very much for your answer