function n = hash(v)
%Computes a hash code for a vector
%The entries of v must be small nonnegative integers

MAXLENGTH = 12;
MODULUS = 997;

l = length(v);
p = primes(40); %length(p) = MAXLENGTH

n = 1;

for i = 1:length(v)
    n = n*p(i)^(v(i) + 1);
    n = mod(n, MODULUS);
end