X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Flibpspp%2Fabt.h;h=3801eb86636c14d2d4a73420329d7c568768d630;hb=0fc5ac957f04c06ab30b990600684d41c68fe1e5;hp=e64ad289304d009d8119b38b162a46b2db66eed4;hpb=93b4335785430ab6de290b7978e2d506106a8ba5;p=pspp-builds.git diff --git a/src/libpspp/abt.h b/src/libpspp/abt.h index e64ad289..3801eb86 100644 --- a/src/libpspp/abt.h +++ b/src/libpspp/abt.h @@ -1,20 +1,18 @@ -/* PSPP - computes sample statistics. +/* PSPP - a program for statistical analysis. Copyright (C) 2007 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or - modify it under the terms of the GNU General Public License as - published by the Free Software Foundation; either version 2 of the - License, or (at your option) any later version. + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. - This program 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 - General Public License for more details. + This program 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 General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301, USA. */ + along with this program. If not, see . */ #ifndef LIBPSPP_ABT_H #define LIBPSPP_ABT_H 1 @@ -27,7 +25,7 @@ part of its data as a function of its immediate children's data. Furthermore, augmented data defined in this way can be efficiently maintained as the tree changes over time. - + For example, suppose we define the "size" of a node as the sum of the "size" of its immediate children, plus 1. In such an annotated BST with height H, we can find the node that would @@ -83,7 +81,7 @@ struct abt_node node; // Embedded binary tree element. int data; // Primary value. int count; // Number of nodes in subtree, - // including this node. + // including this node. }; // Returns the `struct element' that NODE is embedded within. @@ -97,7 +95,7 @@ // strcmp-type return value. static int compare_elements (const struct abt_node *a_, const struct abt_node *b_, - const void *aux) + const void *aux) { const struct element *a = node_to_element (a_); const struct element *b = node_to_element (b_); @@ -111,7 +109,7 @@ reaugment_elements (struct abt_node *node_, const struct abt_node *left, const struct abt_node *right, - const void *aux) + const void *aux) { struct element *node = node_to_element (node_); node->count = 1; @@ -124,16 +122,16 @@ // Finds and returns the element in ABT that is in the given // 0-based POSITION in in-order. static struct element * - find_by_position (struct abt *abt, int position) + find_by_position (struct abt *abt, int position) { struct abt_node *p; - for (p = abt->root; p != NULL; ) + for (p = abt->root; p != NULL; ) { int p_pos = p->down[0] ? node_to_element (p->down[0])->count : 0; if (position == p_pos) return node_to_element (p); else if (position < p_pos) - p = p->down[0]; + p = p->down[0]; else { p = p->down[1]; @@ -160,7 +158,7 @@ ((STRUCT *) ((char *) (NODE) - offsetof (STRUCT, MEMBER))) /* Node in an augmented binary tree. */ -struct abt_node +struct abt_node { struct abt_node *up; /* Parent (NULL for root). */ struct abt_node *down[2]; /* Left child, right child. */ @@ -181,7 +179,7 @@ typedef void abt_reaugment_func (struct abt_node *node, const void *aux); /* An augmented binary tree. */ -struct abt +struct abt { struct abt_node *root; /* Tree's root, NULL if empty. */ abt_compare_func *compare; /* To compare nodes. */