<< "position key: " << setw(16) << pos.key()
<< "\nmaterial key: " << setw(16) << pos.material_key()
<< "\npawn key: " << setw(16) << pos.pawn_key()
<< "position key: " << setw(16) << pos.key()
<< "\nmaterial key: " << setw(16) << pos.material_key()
<< "\npawn key: " << setw(16) << pos.pawn_key()