function v=callopt(u)
S0=10;ex=10;r=0.05;sigma=0.2;T=0.25;
x=S0*exp(norminv(u,r*T-sigma^2*T/2,sigma*sqrt(T)));
v=exp(-r*T)*max(x-ex,0);
%meanCrude=mean(v);
%varCrude=var(v)/length(u);
%meanCrude =
%    0.4626
%varCrude =
%  0.4374