Point(1) = {0, 0, 0, 1};
Point(2) = {1, 0, 0, 1};
Point(3) = {2, 0, 0, 1};
Point(4) = {3, 0, 0, 1};
Line(5) = {1, 2};
Line(6) = {2, 3};
Line(7) = {3, 4};
Physical Line("chocolate") = {5};
Physical Line("chewing-gum") = {6};
Physical Line("candy") = {7};