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Discussion of Problem 1996. Cipher Message 3

What is the minimum number of bits?
Posted by impetus 28 Oct 2013 20:12
I have 3 different understandings of the target value:
1. Whole number of bits in all bytes to be changed to make bit substrings equal (any bit(s) of each byte can be changed);
2. The same as p. 1, but only last consecutive bits of byte (suffix) can be changed;
3. The number from the 0..8 range which is the minimum number of bits that can be changed in all bytes.
Tests do not clarify this. Which one is right?
Re: What is the minimum number of bits?
Posted by Kurpilyansky Eugene (USU) 28 Oct 2013 21:29
It's allowed to change only last bit in every byte.
Re: What is the minimum number of bits?
Posted by impetus 29 Oct 2013 00:48
OK)), thanks!
Re: What is the minimum number of bits?
Posted by IPRIT 2 Aug 2014 17:59
Use the FFTW.