[linuxjm/LDP_man-pages.git] / release / man3 / tsearch.3

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.\" Copyright 1995 by Jim Van Zandt <jrv@vanzandt.mv.com>
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.\" Japanese Version Copyright (c) 1999 ishikawa, keisuke
.\"         all rights reserved.
.\" Translated Tue Mar  9 08:21:04 JST 1999
.\"         by ishikawa, keisuke <ishikawa@sgk.gr.jp>
.\" Updated & Modified Sun Jan 20 11:31:46 JST 2002
.\"         by Yuichi SATO <ysato@h4.dion.ne.jp>
.\"
.TH TSEARCH 3  2008-09-23 "GNU" "Linux Programmer's Manual"
.SH ̾Á°
tsearch, tfind, tdelete, twalk, tdestroy \- ÆóʬÌÚ (binary tree) ¤ÎÁàºî
.SH ½ñ¼°
.nf
.B #include <search.h>
.sp
.BI "void *tsearch(const void *" key ", void **" rootp ,
.BI "                int (*" compar ")(const void *, const void *));"
.sp
.BI "void *tfind(const void *" key ", const void **" rootp ,
.BI "                int (*" compar ")(const void *, const void *));"
.sp
.BI "void *tdelete(const void *" key ", void **" rootp ,
.BI "                int (*" compar ")(const void *, const void *));"
.sp
.BI "void twalk(const void *" root ", void (*" action ")(const void *" nodep ,
.BI "                                   const VISIT " which ,
.BI "                                   const int " depth "));"
.sp
.B #define _GNU_SOURCE
.br
.B #include <search.h>
.sp
.BI "void tdestroy(void *" root ", void (*" free_node ")(void *" nodep ));
.fi
.SH ÀâÌÀ
.BR tsearch (),
.BR tfind (),
.BR twalk (),
.BR tdelete ()
¤Ï
ÆóʬÌÚ¤òÁàºî¤¹¤ë´Ø¿ô¤Ç¤¢¤ë¡£
¤³¤ì¤é¤Î´Ø¿ô¤Ï Knuth (6.2.2) Algorithm T ¤Ë´ð¤Å¤¤¤Æ¤¤¤ë¡£
ÌÚ¹½Â¤¤Ë¤ª¤±¤ë³Æ¥Î¡¼¥É¤ÎºÇ½é¤Î¥Õ¥£¡¼¥ë¥É¤Ï¡¢Âбþ¤¹¤ë¥Ç¡¼¥¿¡¦
¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
(»²¾ÈÀè¤Î¥Ç¡¼¥¿¤Ï¡¢¸Æ¤Ó½Ð¤·¥×¥í¥°¥é¥à¤ÇÍÑ°Õ¤¹¤ë¡£)
\fIcompar\fP ¤ÏÈæ³Ó¥ë¡¼¥Á¥ó¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
Èæ³Ó¥ë¡¼¥Á¥ó¤Ï¡¢¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿ 2 ¤Ä¤ò°ú¿ô¤Ë»ý¤Ä¡£
Èæ³Ó¥ë¡¼¥Á¥ó¤ÎÊÖ¤êÃͤϡ¢1 ¤ÄÌܤΥ¢¥¤¥Æ¥à¤¬ 2 ¤ÄÌܤΥ¢¥¤¥Æ¥à¤è¤ê¤â
¡Ö¾®¤µ¤¤¡¢Åù¤·¤¤¡¢Â礭¤¤¡×¤Ë¤è¤Ã¤Æ¡¢
¡ÖÉé¡¢0¡¢Àµ¡×¤ÎÀ°¿ôÃͤǤʤ±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.PP
.BR tsearch ()
¤Ï¡¢ÌÚ¹½Â¤¤«¤é¥¢¥¤¥Æ¥à¤ò¸¡º÷¤¹¤ë´Ø¿ô¤Ç¤¢¤ë¡£
\fIkey\fP ¤Ï¡¢¸¡º÷¤¹¤ë¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
\fIrootp\fP ¤ÏÌÚ¹½Â¤¤Îº¬¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
ÌÚ¹½Â¤¤¬¥Î¡¼¥É¤ò´Þ¤Þ¤Ê¤¤¾ì¹ç¡¢\fIrootp\fP ¤Î»²¾È¤·¤Æ¤¤¤ëÊÑ¿ô¤Ï
NULL ¤ËÀßÄꤵ¤ì¤Æ¤¤¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
ÌÚ¹½Â¤¤Ë¥¢¥¤¥Æ¥à¤¬¸«¤Ä¤«¤Ã¤¿¾ì¹ç¡¢
.BR tsearch ()
¤Ï¤½¤Î¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
¸«¤Ä¤«¤é¤Ê¤«¤Ã¤¿¾ì¹ç¤Ï¡¢¥¢¥¤¥Æ¥à¤òÌÚ¹½Â¤¤ËÄɲä·¡¢
Äɲä·¤¿¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
.PP
.BR tfind ()
¤Ï¡¢
.BR tsearch ()
¤Ë»÷¤Æ¤¤¤ë¤¬¡¢
¥¢¥¤¥Æ¥à¤¬¸«¤Ä¤«¤é¤Ê¤«¤Ã¤¿¾ì¹ç NULL ¤òÊÖ¤¹ÅÀ¤¬°Û¤Ê¤ë¡£
.PP
.BR tdelete ()
¤ÏÌÚ¹½Â¤¤«¤é¥¢¥¤¥Æ¥à¤òºï½ü¤¹¤ë¡£
°ú¿ô¤Ï
.BR tsearch ()
¤ÈƱ¤¸¤Ç¤¢¤ë¡£
.PP
.BR twalk ()
¤Ï¡¢ÆóʬÌÚ¤ò¿¼¤µÍ¥Àè (depth-first) ¤Ç¡¢
º¸¤«¤é±¦¤Ë¤¿¤É¤Ã¤Æ¤¤¤¯´Ø¿ô¤Ç¤¢¤ë¡£
\fIroot\fP ¤Ïµ¯ÅÀ¤È¤Ê¤ë¥Î¡¼¥É¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
\fIroot\fP ¤Ëº¬°Ê³°¤Î¥Î¡¼¥É¤ò»ØÄꤹ¤ë¤È¡¢ÉôʬÌÚ¤¬ÂоݤȤʤ롣
.BR twalk ()
¤Ï¡¢¥Î¡¼¥É¤òˬ¤ì¤ëÅÙ¤Ë
(¤Ä¤Þ¤ê¡¢ÆâÉô¥Î¡¼¥É¤ËÂФ·¤Æ¤Ï 3 ²ó¡¢ÍÕ¤ËÂФ·¤Æ¤Ï 1 ²ó)
¥æ¡¼¥¶´Ø¿ô \fIaction\fP ¤ò¸Æ¤Ó½Ð¤¹¡£
\fIaction\fP ¤Ë¤Ï°Ê²¼¤Î½ç¤Ë 3 ¤Ä¤Î°ú¿ô¤¬Í¿¤¨¤é¤ì¤ë¡£
ºÇ½é¤Î°ú¿ô¤Ïˬ¤ì¤¿¥Î¡¼¥É¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
2 ¤ÄÌܤΰú¿ô¤Ë¤Ï¡¢ÆâÉô¥Î¡¼¥É¤Î¾ì¹ç¤ÏˬÌä²ó¿ô¤Ë±þ¤¸¤Æ
\fBpreorder\fP, \fBpostorder\fP, \fBendorder\fP ¤¬¡¢
Íդξì¹ç¤Ï \fBleaf\fP ¤¬Í¿¤¨¤é¤ì¤ë¡£
(¤³¤ì¤é¤Î¥·¥ó¥Ü¥ë¤Ï \fI<search.h>\fP ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë¡£)
3 ¤ÄÌܤΰú¿ô¤Ï¥Î¡¼¥É¤Î¿¼¤µ¤Ç¡¢º¬¤Î¾ì¹ç¤Ï 0 ¤Ç¤¢¤ë¡£
.PP
(¤è¤ê°ìÈÌŪ¤Ë¤Ï¡¢\fBpreorder\fP, \fBpostorder\fP, \fBendorder\fP ¤Ï
\fBpreorder\fP, \fBinorder\fP, \fBpostorder\fP ¤È¤·¤ÆÃΤé¤ì¤Æ¤¤¤ë:
¤½¤ì¤¾¤ì¡¢»ÒÍ×ÁǤòé¤ëÁ°¡¦ºÇ½é¤Î»ÒÍ×ÁǤòé¤Ã¤¿¸å¤«¤Ä 2 ÈÖÌܤλÒÍ×ÁǤòé¤ëÁ°¡¦
»ÒÍ×ÁǤòé¤Ã¤¿¸å¤È¤¤¤¦¤³¤È¤òɽ¤·¤Æ¤¤¤ë¡£
¤è¤Ã¤Æ \fBpost\%order\fP ¤È¤¤¤¦Ì¾Á°¤òÁª¤Ö¤Î¤Ï¾¯¤·Ê¶¤é¤ï¤·¤¤¡£)
.PP
.BR tdestroy ()
¤Ï \fIroot\fP ¤¬»Ø¤¹ÌÚ¹½Â¤Á´ÂΤòºï½ü¤·¡¢
.BR tsearch ()
´Ø¿ô¤Ç³ÎÊݤµ¤ì¤¿¥ê¥½¡¼¥¹¤òÁ´¤Æ²òÊü¤¹¤ë¡£
ÌÚ¹½Â¤¤Î³Æ¥Î¡¼¥É¤Ë¤Ä¤¤¤Æ¡¢´Ø¿ô \fIfree_node\fP ¤¬¸Æ¤Ó½Ð¤µ¤ì¤ë¡£
¥Ç¡¼¥¿¤Ø¤Î¥Ý¥¤¥ó¥¿¤¬¤³¤Î´Ø¿ô¤Î°ú¿ô¤È¤·¤ÆÅϤµ¤ì¤ë¡£
¤½¤Î¤è¤¦¤ÊÆ°ºî¤¬É¬ÍפǤʤ±¤ì¤Ð¡¢
\fIfree_node\fP ¤Ï²¿¤â¤·¤Ê¤¤´Ø¿ô¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.SH ÊÖ¤êÃÍ
.BR tsearch ()
¤Ï¡¢ÌÚ¹½Â¤¤Ë¸«¤Ä¤«¤Ã¤¿¥¢¥¤¥Æ¥à¤«¡¢
¿·¤·¤¯Äɲä·¤¿¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
¥á¥â¥ê¤ÎÉÔ­¤Î¤¿¤á¥¢¥¤¥Æ¥à¤òÄɲäǤ­¤Ê¤«¤Ã¤¿¾ì¹ç¤Ï NULL ¤òÊÖ¤¹¡£
.BR tfind ()
¤Ï¡¢¥¢¥¤¥Æ¥à¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
°ìÃפ¹¤ë¥¢¥¤¥Æ¥à¤¬¸«¤Ä¤«¤é¤Ê¤¤¾ì¹ç¤Ï NULL ¤òÊÖ¤¹¡£
¸¡º÷¾ò·ï¤Ë°ìÃפ¹¤ëÍ×ÁǤ¬Ê£¿ô¤¢¤ë¾ì¹ç¡¢ÊÖ¤µ¤ì¤ëÃͤÏÉÔÄê¤Ç¤¢¤ë¡£
.PP
.BR tdelete ()
¤Ïºï½ü¤·¤¿¥¢¥¤¥Æ¥à¤Î¿Æ¤Ø¤Î¥Ý¥¤¥ó¥¿¤òÊÖ¤¹¡£
¥¢¥¤¥Æ¥à¤¬¸«¤Ä¤«¤é¤Ê¤«¤Ã¤¿¾ì¹ç¤Ï NULL ¤òÊÖ¤¹¡£
.PP
\fIrootp\fP ¤¬ NULL ¤Î¾ì¹ç¡¢
.BR tsearch (),
.BR tfind (),
.BR tdelete ()
¤Ï NULL ¤òÊÖ¤¹¡£
.SH ½àµò
SVr4, POSIX.1-2001.
´Ø¿ô
.BR tdestroy ()
¤Ï GNU ¤Î³ÈÄ¥¤Ç¤¢¤ë¡£
.SH Ãí°Õ
.BR twalk ()
¤Ïº¬¤Ø¤Î¥Ý¥¤¥ó¥¿¤ò°ú¿ô¤Ë¤È¤ë¤¬¡¢
¤Û¤«¤Î´Ø¿ô¤Ïº¬¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ø¤Î¥Ý¥¤¥ó¥¿¤Ç¤¢¤ë¡£
.PP
.BR twalk ()
¤Ë¤ª¤¤¤Æ¤Ï¡¢\fBpostorder\fP ¤Ï
¡Öº¸¤ÎÉôʬÌڤθå¤Ç¡¢±¦¤ÎÉôʬÌÚ¤ÎÁ°¡×¤ò°ÕÌ£¤·¤Æ¤¤¤ë¡£
¤·¤«¤·¡¢¿Í¤Ë¤è¤Ã¤Æ¤Ï¤³¤ì¤ò "inorder" ¤È¸Æ¤ó¤Ç¡¢
"postorder" ¤ò¡ÖξÊý¤ÎÉôʬÌڤθå¡×¤È¤¹¤ë¾ì¹ç¤â¤¢¤ë¡£
.PP
.BR tdelete ()
¤Ï¡¢ºï½ü¤·¤¿¥Î¡¼¥É¤Î»ÈÍѤ·¤Æ¤¤¤¿¥á¥â¥ê¤ò²òÊü¤¹¤ë¤¬¡¢
¥Î¡¼¥É¤ËÂбþ¤¹¤ë¥Ç¡¼¥¿¤Î¥á¥â¥ê¤Ï¡¢¥æ¡¼¥¶¤¬²òÊü¤·¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤¡£
.PP
²¼¤Î¥×¥í¥°¥é¥àÎã¤Ï¡¢¥æ¡¼¥¶´Ø¿ô¤¬ "endorder" ¤« "leaf" ¤ò°ú¿ô¤Ë¤·¤Æ
¸Æ¤Ó½Ð¤µ¤ì¤Æ°Ê¹ß¤Ï¡¢
.BR twalk ()
¤¬¤½¤Î¥Î¡¼¥É¤ò»²¾È¤·¤Ê¤¤¤³¤È¤òÁ°Äó¤È¤·¤Æ¤¤¤ë¡£
¤³¤ì¤Ï GNU ¥é¥¤¥Ö¥é¥ê¤Î¼ÂÁõ¤Ç¤Ïµ¡Ç½¤¹¤ë¤¬¡¢System V ¤Î¥Þ¥Ë¥å¥¢¥ë¤Ë¤Ï¸ºß¤·¤Ê¤¤¡£
.SH Îã
°Ê²¼¤Î¥×¥í¥°¥é¥à¤Ï 12 ¸Ä¤ÎÍð¿ô¤òÆóʬÌÚ¤ËÁÞÆþ¤·¤¿¸å¡¢
ÁÞÆþ¤·¤¿¿ô¤ò½çÈ֤˽ÐÎϤ¹¤ë (ÁÞÆþ¤ÎºÝ¡¢½ÅÊ£¤·¤¿Íð¿ô¤Ï 1 ¤Ä¤Ë¤Þ¤È¤á¤é¤ì¤ë)¡£
.sp
.nf
#define _GNU_SOURCE     /* Expose declaration of tdestroy() */
#include <search.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>

void *root = NULL;

void *
xmalloc(unsigned n)
{
    void *p;
    p = malloc(n);
    if (p)
        return p;
    fprintf(stderr, "insufficient memory\\n");
    exit(EXIT_FAILURE);
}

int
compare(const void *pa, const void *pb)
{
    if (*(int *) pa < *(int *) pb)
        return \-1;
    if (*(int *) pa > *(int *) pb)
        return 1;
    return 0;
}

void
action(const void *nodep, const VISIT which, const int depth)
{
    int *datap;

    switch (which) {
    case preorder:
        break;
    case postorder:
        datap = *(int **) nodep;
        printf("%6d\\n", *datap);
        break;
    case endorder:
        break;
    case leaf:
        datap = *(int **) nodep;
        printf("%6d\\n", *datap);
        break;
    }
}

int
main(void)
{
    int i, *ptr;
    void *val;

    srand(time(NULL));
    for (i = 0; i < 12; i++) {
        ptr = (int *) xmalloc(sizeof(int));
        *ptr = rand() & 0xff;
        val = tsearch((void *) ptr, &root, compare);
        if (val == NULL)
            exit(EXIT_FAILURE);
        else if ((*(int **) val) != ptr)
            free(ptr);
    }
    twalk(root, action);
    tdestroy(root, free);
    exit(EXIT_SUCCESS);
}
.fi
.SH ´ØÏ¢¹àÌÜ
.BR bsearch (3),
.BR hsearch (3),
.BR lsearch (3)
.BR qsort (3),
.BR feature_test_macros (7)