function prodsumcheck

global miny
miny = 1;

while 1
  x = rand(4,1);
  [x,fval] = fmincon(@ps,x,[],[],[],[],0*x,0*x+1);
end


return



function y = ps(x)
a1 = x(1);
a2 = x(2);
b1 = x(3);
b2 = x(4);

y = abs(a1-b1)+abs(a2-b2) - abs(a1*a2-b1*b2);

global miny
if y<miny
  miny = y;
  global mx
  mx = x;
end
fprintf('miny = %1.8f \n',miny);

return