How can I efficiently store binary codes? For certain fixed sizes, such as 32 bits, there are primitive types that can be used. But what if I my binary codes are much longer?
What is the fastest way to compute the Hamming distance between two binary codes?
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Timothy Shields
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mrgloom
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What about std::bitset? – Niall Oct 02 '14 at 20:14
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std::bitset<N>, defined in the<bitset>header, whereNis the number of bits (not bytes). - Compute the Hamming distance between two binary codes
aandbusing(a ^ b).count().
Timothy Shields
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I don't understand what if use 30 bit codes I still can use 32bit integer?(maybe mask 2 first bits somehow)? – mrgloom Oct 02 '14 at 20:36
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@mrgloom I would use this approach, profile it, and then only if you determine it is too slow look at doing something custom. My understanding is that a `std::bitset<30>` will only use 4 bytes of storage. – Timothy Shields Oct 02 '14 at 20:41
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Nice Timothy, maybe you can help with [XOR bitset when 2D bitset is stored as 1D](http://stackoverflow.com/questions/40787731/xor-bitset-when-2d-bitset-is-stored-as-1d). – gsamaras Nov 24 '16 at 13:32