function d=diam(X)
d=0;
for i=1:length(X)
  for j=i+1:length(X)
    %xi=X{i}
    %xj=X{j}
    %rij = rho(X{i},X{j})
    d = max(d,rho(X{i},X{j}));
  end
end
return


function r=rho(x,y)
r = length(find(x~=y));
return