The main character of The Pianist survives due to the help of a German army captain, who was taken prisoner by what army?
The Pianist (memoir):  He survives in the ruined city with the help of friends and strangers, including Wilm Hosenfeld, a German army captain who admires his piano playing. Wilm Hosenfeld:  He was taken prisoner by the Red Army and died in Soviet captivity seven years later.
Red Army