function y=testif_2(a,b) 
%Ypologismos arithmitikwn timwn poluwnumwn
switch a
case 3
y=3*b^2+2*b+1;
case 4
y=4*b^3+3*b^2+2*b+1;
otherwise
y=2*b+1;
end

% H epalitheusi ginetai pliktrologwntas:
% y=testif_2(0,-1)
% y =
% -1
