btree_find_leaf_i8_zp2d Subroutine

      SUBROUTINE btree_find_leaf_i8_zp2d (tree, key, node, gti)
         TYPE(btree_i8_zp2d), INTENT(IN) :: tree
         INTEGER(KIND=keyt), INTENT(IN) :: key
         TYPE(btree_node_i8_zp2d), POINTER :: node
         INTEGER, INTENT(OUT) :: gti
         !
         NULLIFY (node)
         !IF (tree%b%n .EQ. 0) RETURN
         IF (.NOT. ASSOCIATED(tree%b%root)) RETURN
         gti = 1
         ! Try to find the key in the given node. If it's found, then
         ! return the node.
         node => tree%b%root
         descent: DO WHILE (.TRUE.)
            ! Try to find the first element equal to or greater than the
            ! one we're searching for.
            !CALL btree_node_find_ge_pos_i8_zp2d (node%keys, key, position, node%filled)
            ! One of three things is now true about position: it's now
            ! greater than the number of keys (if all keys are smaller), or
            ! it points to the key that is equal to or greater than the one
            ! we are searching for. If it is found and we are just
            ! searching for one equal element (i.e., user search), we can
            ! return.
            !
            ! If the key is not found, then either return the GE position
            ! if we're in a leaf (case 2 here), otherwise descend into the
            ! subtrees.
            CALL btree_node_find_gt_pos_i8_zp2d (node%keys, key, gti, node%filled)
            !CALL btree_node_find_gt2_pos_i8_zp2d (node%keys, key, i, node%filled)
            !IF (i .NE. gti) WRITE(*,*)'XXXX difference',i,gti
            IF (ASSOCIATED(node%subtrees(1)%node)) THEN
               node => node%subtrees(gti)%node
            ELSE
               RETURN
            END IF
         END DO descent
      END SUBROUTINE btree_find_leaf_i8_zp2d