def add_leaves(self, values_array, do_hash=False):
        """
        Add leaves to the tree.

        Similar to chainpoint merkle tree library, this accepts hash values as an array of Buffers or hex strings.
        :param values_array: array of values to add
        :param do_hash: whether to hash the values before inserting
        """
        self.tree['is_ready'] = False
        [self._add_leaf(value, do_hash) for value in values_array]