mirror of https://gitee.com/openkylin/glib2.0.git
99 lines
2.1 KiB
C
99 lines
2.1 KiB
C
/* GLIB - Library of useful routines for C programming
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* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
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*
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* SPDX-License-Identifier: LGPL-2.1-or-later
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* Modified by the GLib Team and others 1997-2000. See the AUTHORS
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* file for a list of people on the GLib Team. See the ChangeLog
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* files for a list of changes. These files are distributed with
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* GLib at ftp://ftp.gtk.org/pub/gtk/.
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*/
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/*
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* MT safe
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*/
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#include "config.h"
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#include "gprimes.h"
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static const guint g_primes[] =
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{
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11,
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19,
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37,
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73,
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109,
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163,
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251,
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367,
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557,
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823,
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1237,
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1861,
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2777,
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4177,
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6247,
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9371,
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14057,
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21089,
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31627,
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47431,
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71143,
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106721,
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160073,
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240101,
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360163,
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540217,
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810343,
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1215497,
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1823231,
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2734867,
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4102283,
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6153409,
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9230113,
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13845163,
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};
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/**
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* g_spaced_primes_closest:
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* @num: a #guint
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*
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* Gets the smallest prime number from a built-in array of primes which
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* is larger than @num. This is used within GLib to calculate the optimum
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* size of a #GHashTable.
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*
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* The built-in array of primes ranges from 11 to 13845163 such that
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* each prime is approximately 1.5-2 times the previous prime.
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*
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* Returns: the smallest prime number from a built-in array of primes
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* which is larger than @num
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*/
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guint
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g_spaced_primes_closest (guint num)
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{
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gsize i;
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for (i = 0; i < G_N_ELEMENTS (g_primes); i++)
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if (g_primes[i] > num)
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return g_primes[i];
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return g_primes[G_N_ELEMENTS (g_primes) - 1];
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}
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