/* List implementation of a partition of consecutive integers.   Copyright (C) 2000-2026 Free Software Foundation, Inc.   Contributed by CodeSourcery, LLC.    This file is part of GCC.    GCC 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, or (at your option)   any later version.    GCC 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 GCC; see the file COPYING.  If not, write to   the Free Software Foundation, 51 Franklin Street - Fifth Floor,   Boston, MA 02110-1301, USA.  */ /* This package implements a partition of consecutive integers.  The   elements are partitioned into classes.  Each class is represented   by one of its elements, the canonical element, which is chosen   arbitrarily from elements in the class.  The principal operations   on a partition are FIND, which takes an element, determines its   class, and returns the canonical element for that class, and UNION,   which unites the two classes that contain two given elements into a   single class.    The list implementation used here provides constant-time finds.  By   storing the size of each class with the class's canonical element,   it is able to perform unions over all the classes in the partition   in O (N log N) time.  */ #ifndef _PARTITION_H#define _PARTITION_H #ifdef __cplusplusextern "C" {#endif /* __cplusplus */ #include "ansidecl.h"#include <stdio.h> struct partition_elem{  /* The next element in this class.  Elements in each class form a     circular list.  */  struct partition_elem* next;  /* The canonical element that represents the class containing this     element.  */  int class_element;  /* The number of elements in this class.  Valid only if this is the     canonical element for its class.  */  unsigned class_count;}; typedef struct partition_def {  /* The number of elements in this partition.  */  int num_elements;  /* The elements in the partition.  */  struct partition_elem elements[1];} *partition; extern partition partition_new (int);extern void partition_delete (partition);extern int partition_union (partition, int, int);extern void partition_print (partition,	FILE*); /* Returns the canonical element corresponding to the class containing   ELEMENT__ in PARTITION__.  */ #define partition_find(partition__, element__) \    ((partition__)->elements[(element__)].class_element) #ifdef __cplusplus}#endif /* __cplusplus */ #endif /* _PARTITION_H */