XT:=ContractedComplex(XT);;
CriticalCells(XT);;
H0:=Homology(XT,0);
H1:=Homology(XT,1);
H2:=Homology(XT,2);
H3:=Homology(XT,3);
H4:=Homology(XT,4);
F:=FundamentalGroup(XT);
RelatorsOfFpGroup(F); 

SY:=ContractedComplex(SY);;
CriticalCells(SY);;
h1:=Homology(SY,0);
h1:=Homology(SY,1);
h2:=Homology(SY,2);
h3:=Homology(SY,3);
h4:=Homology(SY,4);
f:=FundamentalGroup(SY);
RelatorsOfFpGroup(f);

Print("Example runtime :", StringTime(Runtime()-RT), "\n\n");