  The $dp\to dp$ and $dd\to ^3He n$ reactions are considered in the energy
range from few hundred MeV up to 1 GeV. The approach is based on the
multiple-scattering theory, where the few-body collisions are presented through
two-body ones. The high-energy nucleon-nucleon interactions are described by
t-matrix, which is parameterized in accordance with the modern phase-shift
analysis data. The special attention is given to investigation of the
rescattering effects in these reactions.
  The theoretical predictions are obtained for the differential cross sections,
vector and tensor analyzing powers. All results are presented in comparison
with the existing experimental data.
