mdp

module one
	x : [0 .. 2] init 0;

	[a] x=0 -> (x'=1);
	[] x>=0 -> (x'=2);
	[done] x>=1 -> true;
endmodule

module two
	y : [0 .. 2] init 0;

	[b] y=0 -> (y'=1);
	[] y>=0 -> (y'=2);
	[done] y>=1 -> true;
endmodule

module three
	z : [0 .. 2] init 0;

	[a] z=0 -> (z'=1);
	[] x=0&y=0&z=1 -> (z'=2);
	[loop] z>=1 -> true;
endmodule

system
	((one || two {b <- a})) {done <- loop} || three
endsystem