Place 1 king, 2 queens, and 5 knights on a standard 8×8 chessboard so that every unoccupied square is under attack.
One of the valid arrangements is:
Q x x x x x x x
x x x x x x x x Q-> Queen
x x x x n x x x
x x x n n x x x K -> King
x x x n n x x x n -> knight
x x x x x x x x
x x K x x x x x
x x x x x x x Q
Edited on January 30, 2023, 2:21 am