function s104021119()
format long
x=[0.3 0.4 0.5 0.6];
f = [exp(-2*0.3) exp(-2*0.4) exp(-2*0.5) exp(-2*0.6)];
y = f-x;
n = 3;
Q = zeros(3+1);
Q(:,1) = x';
z=0;
i=1;
while i<=n
   j=1;
   while j<=i
      Q(i+1,j+1) = ((z-y(i-j+1))*(Q(i+1,j))-(z-y(i+1))*Q(i,j))/(y(i+1)-y(i-j+1));
      j++;
   end
   i++;
end

Q(n+1,n+1)
a = Q(n+1,n+1);
a-exp(-2*a)
if(a<10^(-3)) printf("true");
else printf("F");
end