//load "PETSc" load "iovtk" mesh Th = square(200, 200); real x0 = 0.48; real x1 = 0.52; real y0 = 0.98; real y1 = 1; int n = 5; real m = 5; int[int] labs = [11, 12, 13, 14]; mesh Th2 = square(n, m, [x0+(x1-x0)*x, y0+(y1-y0)*y], label=labs,region=10); mesh Th1=Th+Th2; cout<<"labels(Th1)="<