function p = sym_perm(n, A, B)
%A should be a matrix that contains the numbers 1 through n, once each, and
%have all other entries zero.  B should be the same as A except that the
%nonzero entries are permuted.  Function returns a 1xn vector representing
%the permutation.
[l, w] = size(A);
for i = 1:l
    for j = 1:w
        if A(i, j)
            p(A(i, j)) = B(i, j);
        end
    end
end