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#include "Bitvec.h"
#include <vector>
#include <assert.h>
// handle xnor
typedef std::vector<uint32_t> slice;
typedef std::vector<slice> slice_vec;
int countbits ( slice & v )
{
int c = 0;
for(size_t i = 0; i < v.size(); i++)
{
int d = countbits(v[i]);
c += d;
}
return c;
}
int countxor ( slice & a, slice & b )
{
assert(a.size() == b.size());
int c = 0;
for(size_t i = 0; i < a.size(); i++)
{
int d = countbits(a[i] ^ b[i]);
c += d;
}
return c;
}
void xoreq ( slice & a, slice & b )
{
assert(a.size() == b.size());
for(size_t i = 0; i < a.size(); i++)
{
a[i] ^= b[i];
}
}
//-----------------------------------------------------------------------------
// Bitslice a hash set
template< typename hashtype >
void Bitslice ( std::vector<hashtype> & hashes, slice_vec & slices )
{
const int hashbytes = sizeof(hashtype);
const int hashbits = hashbytes * 8;
const int slicelen = ((int)hashes.size() + 31) / 32;
slices.clear();
slices.resize(hashbits);
for(int i = 0; i < (int)slices.size(); i++)
{
slices[i].resize(slicelen,0);
}
for(int j = 0; j < hashbits; j++)
{
void * sliceblob = &(slices[j][0]);
for(int i = 0; i < (int)hashes.size(); i++)
{
int b = getbit(hashes[i],j);
setbit(sliceblob,slicelen*4,i,b);
}
}
}
void FactorSlices ( slice_vec & slices )
{
std::vector<int> counts(slices.size(),0);
for(size_t i = 0; i < slices.size(); i++)
{
counts[i] = countbits(slices[i]);
}
bool changed = true;
while(changed)
{
int bestA = -1;
int bestB = -1;
for(int j = 0; j < (int)slices.size()-1; j++)
{
for(int i = j+1; i < (int)slices.size(); i++)
{
int d = countxor(slices[i],slices[j]);
if((d < counts[i]) && (d < counts[j]))
{
if(counts[i] < counts[j])
{
bestA = j;
bestB = i;
}
}
else if(d < counts[i])
{
//bestA =
}
}
}
}
}
void foo ( void )
{
slice a;
slice_vec b;
Bitslice(a,b);
}