```      SUBROUTINE SLASDT( N, LVL, ND, INODE, NDIML, NDIMR, MSUB )
*
*  -- LAPACK auxiliary routine (version 3.1) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2006
*
*     .. Scalar Arguments ..
INTEGER            LVL, MSUB, N, ND
*     ..
*     .. Array Arguments ..
INTEGER            INODE( * ), NDIML( * ), NDIMR( * )
*     ..
*
*  Purpose
*  =======
*
*  SLASDT creates a tree of subproblems for bidiagonal divide and
*  conquer.
*
*  Arguments
*  =========
*
*   N      (input) INTEGER
*          On entry, the number of diagonal elements of the
*          bidiagonal matrix.
*
*   LVL    (output) INTEGER
*          On exit, the number of levels on the computation tree.
*
*   ND     (output) INTEGER
*          On exit, the number of nodes on the tree.
*
*   INODE  (output) INTEGER array, dimension ( N )
*          On exit, centers of subproblems.
*
*   NDIML  (output) INTEGER array, dimension ( N )
*          On exit, row dimensions of left children.
*
*   NDIMR  (output) INTEGER array, dimension ( N )
*          On exit, row dimensions of right children.
*
*   MSUB   (input) INTEGER.
*          On entry, the maximum row dimension each subproblem at the
*          bottom of the tree can be of.
*
*  Further Details
*  ===============
*
*  Based on contributions by
*     Ming Gu and Huan Ren, Computer Science Division, University of
*     California at Berkeley, USA
*
*  =====================================================================
*
*     .. Parameters ..
REAL               TWO
PARAMETER          ( TWO = 2.0E+0 )
*     ..
*     .. Local Scalars ..
INTEGER            I, IL, IR, LLST, MAXN, NCRNT, NLVL
REAL               TEMP
*     ..
*     .. Intrinsic Functions ..
INTRINSIC          INT, LOG, MAX, REAL
*     ..
*     .. Executable Statements ..
*
*     Find the number of levels on the tree.
*
MAXN = MAX( 1, N )
TEMP = LOG( REAL( MAXN ) / REAL( MSUB+1 ) ) / LOG( TWO )
LVL = INT( TEMP ) + 1
*
I = N / 2
INODE( 1 ) = I + 1
NDIML( 1 ) = I
NDIMR( 1 ) = N - I - 1
IL = 0
IR = 1
LLST = 1
DO 20 NLVL = 1, LVL - 1
*
*        Constructing the tree at (NLVL+1)-st level. The number of
*        nodes created on this level is LLST * 2.
*
DO 10 I = 0, LLST - 1
IL = IL + 2
IR = IR + 2
NCRNT = LLST + I
NDIML( IL ) = NDIML( NCRNT ) / 2
NDIMR( IL ) = NDIML( NCRNT ) - NDIML( IL ) - 1
INODE( IL ) = INODE( NCRNT ) - NDIMR( IL ) - 1
NDIML( IR ) = NDIMR( NCRNT ) / 2
NDIMR( IR ) = NDIMR( NCRNT ) - NDIML( IR ) - 1
INODE( IR ) = INODE( NCRNT ) + NDIML( IR ) + 1
10    CONTINUE
LLST = LLST*2
20 CONTINUE
ND = LLST*2 - 1
*
RETURN
*
*     End of SLASDT
*
END

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