Let \( A = \{-4, -3, -2, 0, 1, 3, 4\} \) and \( R = \{(a, b) \in A \times A : b = |a| \text{ or } b^2 = a + 1\} \) be a relation on \( A \). Then the minimum number of elements, that must be added to the relation \( R \) so that it becomes reflexive and symmetric, is _________.
