37 lines
1.1 KiB
C++
37 lines
1.1 KiB
C++
/*
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Copyright (C) 1990 Free Software Foundation
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written by Doug Lea (dl@rocky.oswego.edu)
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This file is part of the GNU C++ Library. This library is free
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software; you can redistribute it and/or modify it under the terms of
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the GNU Library General Public License as published by the Free
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Software Foundation; either version 2 of the License, or (at your
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option) any later version. This library is distributed in the hope
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that it will be useful, but WITHOUT ANY WARRANTY; without even the
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implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
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PURPOSE. See the GNU Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with this library; if not, write to the Free Software
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Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#include <hash.h>
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/*
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some useful hash functions
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*/
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unsigned int hashpjw (const char* x) // From Dragon book, p436
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{
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unsigned int h = 0;
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unsigned int g;
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while (*x != 0)
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{
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h = (h << 4) + (unsigned char) *x++;
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if ((g = h & 0xf0000000) != 0)
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h = (h ^ (g >> 24)) ^ g;
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}
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return h;
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}
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