public bool MappingPhase(out uint hashSeed, out uint maxBucketSize)
{
var hl = new uint[3];
var mapItems = new MapItem[_m];
uint mappingIterations = 1000;
var rdm = new Random(111);
maxBucketSize = 0;
for (; ;)
{
mappingIterations--;
hashSeed = (uint)rdm.Next((int)_m); // ((cmph_uint32)rand() % this->_m);
BucketsClean();
_keySource.Rewind();
uint i;
for (i = 0; i < _m; i++)
{
JenkinsHash.HashVector(hashSeed, _keySource.Read(), hl);
uint g = hl[0] % _nbuckets;
mapItems[i].F = hl[1] % _n;
mapItems[i].H = hl[2] % (_n - 1) + 1;
mapItems[i].BucketNum = g;
_buckets[g].Size++;
if (_buckets[g].Size > maxBucketSize)
{
maxBucketSize = _buckets[g].Size;
}
}
_buckets[0].ItemsList = 0;
for (i = 1; i < _nbuckets; i++)
{
_buckets[i].ItemsList = _buckets[i - 1].ItemsList + _buckets[i - 1].Size;
_buckets[i - 1].Size = 0;
}
_buckets[i - 1].Size = 0;
for (i = 0; i < _m; i++)
{
if (!BucketsInsert(mapItems, i))
{
break;
}
}
if (i == _m)
{
return(true); // SUCCESS
}
if (mappingIterations == 0)
{
return(false);
}
}
}
/// <summary>
/// Compute the hash value associate with the key
/// </summary>
/// <param name="key">key from the original key set</param>
/// <returns>Hash value (0 > hash > N)</returns>
public uint Search(byte[] key)
{
var hl = new uint[3];
JenkinsHash.HashVector(this._hashSeed, key, hl);
var g = hl[0] % this._nbuckets;
var f = hl[1] % this._n;
var h = hl[2] % (this._n - 1) + 1;
var disp = this._cs.Query(g);
var probe0Num = disp % this._n;
var probe1Num = disp / this._n;
var position = (uint)((f + ((ulong)h) * probe0Num + probe1Num) % this._n);
return(position);
}
