1 | /*
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2 | * Copyright (c) 1989 The Regents of the University of California.
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3 | * All rights reserved.
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4 | *
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5 | * This code is derived from software contributed to Berkeley by
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6 | * Robert Paul Corbett.
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7 | *
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8 | * Redistribution and use in source and binary forms, with or without
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9 | * modification, are permitted provided that the following conditions
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10 | * are met:
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11 | * 1. Redistributions of source code must retain the above copyright
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12 | * notice, this list of conditions and the following disclaimer.
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13 | * 2. Redistributions in binary form must reproduce the above copyright
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14 | * notice, this list of conditions and the following disclaimer in the
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15 | * documentation and/or other materials provided with the distribution.
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16 | * 3. All advertising materials mentioning features or use of this software
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17 | * must display the following acknowledgement:
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18 | * This product includes software developed by the University of
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19 | * California, Berkeley and its contributors.
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20 | * 4. Neither the name of the University nor the names of its contributors
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21 | * may be used to endorse or promote products derived from this software
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22 | * without specific prior written permission.
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23 | *
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24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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34 | * SUCH DAMAGE.
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35 | */
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36 |
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37 | #if 0
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38 | #ifndef lint
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39 | static char sccsid[] = "@(#)warshall.c 5.4 (Berkeley) 5/24/93";
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40 | #endif
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41 | #endif
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42 |
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43 | #include <sys/cdefs.h>
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44 | __FBSDID("$FreeBSD: src/usr.bin/yacc/warshall.c,v 1.12 2002/04/09 11:39:05 ru Exp $");
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45 |
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46 | #include "defs.h"
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47 |
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48 | static void transitive_closure(unsigned *, int);
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49 |
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50 | static void
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51 | transitive_closure(R, n)
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52 | unsigned *R;
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53 | int n;
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54 | {
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55 | int rowsize;
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56 | unsigned i;
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57 | unsigned *rowj;
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58 | unsigned *rp;
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59 | unsigned *rend;
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60 | unsigned *ccol;
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61 | unsigned *relend;
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62 | unsigned *cword;
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63 | unsigned *rowi;
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64 |
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65 | rowsize = WORDSIZE(n);
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66 | relend = R + n*rowsize;
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67 |
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68 | cword = R;
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69 | i = 0;
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70 | rowi = R;
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71 | while (rowi < relend)
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72 | {
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73 | ccol = cword;
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74 | rowj = R;
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75 |
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76 | while (rowj < relend)
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77 | {
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78 | if (*ccol & (1 << i))
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79 | {
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80 | rp = rowi;
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81 | rend = rowj + rowsize;
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82 | while (rowj < rend)
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83 | *rowj++ |= *rp++;
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84 | }
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85 | else
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86 | {
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87 | rowj += rowsize;
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88 | }
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89 |
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90 | ccol += rowsize;
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91 | }
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92 |
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93 | if (++i >= BITS_PER_WORD)
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94 | {
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95 | i = 0;
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96 | cword++;
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97 | }
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98 |
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99 | rowi += rowsize;
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100 | }
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101 | }
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102 |
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103 | void
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104 | reflexive_transitive_closure(R, n)
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105 | unsigned *R;
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106 | int n;
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107 | {
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108 | int rowsize;
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109 | unsigned i;
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110 | unsigned *rp;
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111 | unsigned *relend;
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112 |
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113 | transitive_closure(R, n);
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114 |
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115 | rowsize = WORDSIZE(n);
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116 | relend = R + n*rowsize;
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117 |
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118 | i = 0;
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119 | rp = R;
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120 | while (rp < relend)
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121 | {
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122 | *rp |= (1 << i);
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123 | if (++i >= BITS_PER_WORD)
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124 | {
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125 | i = 0;
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126 | rp++;
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127 | }
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128 |
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129 | rp += rowsize;
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130 | }
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131 | }
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