function Err = error_check_a3(C1,C2)

n = length(C1); % This n should be 30 one for each point
Err = 0; % start counter at 0
for t = 1:n
Err = Err + abs(C1(t) ~=C2(t))/n; % increase error by 1 if the two clustering disagree.
end
Err = min([Err,1-Err]); % error is the smaller of Err or 1 - Err