# Omega Calculator v1.2 (based on Omega Library 1.2, August, 2000):
# R := {[1:10,1:10]} union {[-10:-1,-10:-1]} union
# 	{[x,y] : -10 <= x,y <= 10 && -10 <= x-y <= 10};
# 
# R;

{[x,y]: -10, y-10 <= x <= 10, y+10 && -10 <= y <= 10}

# 
# Hull R;

{[x,y]: -10, y-10 <= x <= 10, y+10 && -10 <= y <= 10}

#