/*
* CXSPARSE: a Concise Sparse Matrix package - Extended.
* Copyright (c) 2006-2009, Timothy A. Davis.
* http://www.cise.ufl.edu/research/sparse/CXSparse
*
* CXSparse is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* CXSparse is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this Module; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "cs.h"
/* depth-first search and postorder of a tree rooted at node j */
CS_INT cs_tdfs (CS_INT j, CS_INT k, CS_INT *head, const CS_INT *next, CS_INT *post, CS_INT *stack)
{
CS_INT i, p, top = 0 ;
if (!head || !next || !post || !stack) return (-1) ; /* check inputs */
stack [0] = j ; /* place j on the stack */
while (top >= 0) /* while (stack is not empty) */
{
p = stack [top] ; /* p = top of stack */
i = head [p] ; /* i = youngest child of p */
if (i == -1)
{
top-- ; /* p has no unordered children left */
post [k++] = p ; /* node p is the kth postordered node */
}
else
{
head [p] = next [i] ; /* remove i from children of p */
stack [++top] = i ; /* start dfs on child node i */
}
}
return (k) ;
}