Start:
P0 P1 P2 P3 P4
Next:
P1 P2 P3 P4
P0
Next (reverse):
P4 P3 P2 P1 P0
Next:
P2 P1 P0
P3 P4
Next:
P0 P1 P2 P3 P4
Next:
P3 P4
P2 P1 P0
Next:
P4 P3 P2 P1 P0
Next:
P0
P1 P2 P3 P4
End of round