function V=MCarlo(S0,X,R,T,SIG,NSteps,NRepl)
DeltaT = T/NSteps;
Counter = 0.0;
%R=1+R;
for i=1:NRepl
   S=S0;
   for j=1:NSteps
      S=S*(1+R*DeltaT + SIG*randn*sqrt(DeltaT));
   end
   Counter = Counter + max(0,S-X);
end
V=exp(-R*T)*Counter/NRepl;