inline void join( const BlockedRangeWDPReducer<WDPin> &other ) {
wd.result = wd.reduce( wd.result, other.wd.result );
}
void operator()(tbb::blocked_range<int> &rng)
{
for(int i=rng.begin(); i<rng.end(); ++i) {
wd.result = wd.reduce(wd.result, wd.generate(i));
}
}