| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: factorial.c,v 1.3 2002/01/13 19:51:59 mdw Exp $ |
| 4 | * |
| 5 | * Example factorial computation |
| 6 | * |
| 7 | * (c) 2000 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Catacomb. |
| 13 | * |
| 14 | * Catacomb is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU Library General Public License as |
| 16 | * published by the Free Software Foundation; either version 2 of the |
| 17 | * License, or (at your option) any later version. |
| 18 | * |
| 19 | * Catacomb is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU Library General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU Library General Public |
| 25 | * License along with Catacomb; if not, write to the Free |
| 26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Revision history --------------------------------------------------* |
| 31 | * |
| 32 | * $Log: factorial.c,v $ |
| 33 | * Revision 1.3 2002/01/13 19:51:59 mdw |
| 34 | * Provide proper help and options parsing. Allow more bases. Use |
| 35 | * @mptext@ to read integers for the better base support. |
| 36 | * |
| 37 | * Revision 1.2 2001/06/16 13:22:59 mdw |
| 38 | * Added command-line option to select output radix. |
| 39 | * |
| 40 | * Revision 1.1 2000/07/09 21:30:49 mdw |
| 41 | * Demo program to compute factorials. |
| 42 | * |
| 43 | */ |
| 44 | |
| 45 | /*----- Header files ------------------------------------------------------*/ |
| 46 | |
| 47 | #include "config.h" |
| 48 | |
| 49 | #include <ctype.h> |
| 50 | #include <limits.h> |
| 51 | #include <stdio.h> |
| 52 | #include <stdlib.h> |
| 53 | |
| 54 | #include <mLib/mdwopt.h> |
| 55 | #include <mLib/quis.h> |
| 56 | #include <mLib/report.h> |
| 57 | |
| 58 | #include "mpint.h" |
| 59 | #include "mpmul.h" |
| 60 | #include "mptext.h" |
| 61 | |
| 62 | /*----- Main code ---------------------------------------------------------*/ |
| 63 | |
| 64 | static void usage(FILE *fp) |
| 65 | { |
| 66 | pquis(fp, "Usage: $ [-r radix] integer\n"); |
| 67 | } |
| 68 | |
| 69 | static void version(FILE *fp) |
| 70 | { |
| 71 | pquis(fp, "$, Catacomb version " VERSION "\n"); |
| 72 | } |
| 73 | |
| 74 | static void help(FILE *fp) |
| 75 | { |
| 76 | version(fp); |
| 77 | putc('\n', fp); |
| 78 | usage(fp); |
| 79 | fputs("\n\ |
| 80 | Prints the factorial of the given integer on its output. Input may be\n\ |
| 81 | in decimal (the default), octal with preceding zero, hex with preceding\n\ |
| 82 | `0x', or any base N between 2 and 62 inclusive with preceding `N_'.\n\ |
| 83 | Output may be in any base between 2 and 62; the default is base 10. For\n\ |
| 84 | bases between 11 and 36 inclusive, lowercase letters of either case are\n\ |
| 85 | used as additional digits with values 10 upwards; lowercase is always\n\ |
| 86 | used for output. For bases between 37 and 62 inclusive, lowercase letters\n\ |
| 87 | have lower value than uppercase; hence `a' has the value 10, while `A' has\n\ |
| 88 | the value 36.\n\ |
| 89 | \n\ |
| 90 | Options provided:\n\ |
| 91 | \n\ |
| 92 | -h, --help Display this help message.\n\ |
| 93 | -v, --version Display the version number.\n\ |
| 94 | -u, --usage Display a usage message.\n\ |
| 95 | \n\ |
| 96 | -r, --radix=N Write output in base N.\n\ |
| 97 | ", fp); |
| 98 | } |
| 99 | |
| 100 | int main(int argc, char *argv[]) |
| 101 | { |
| 102 | unsigned long x; |
| 103 | int r = 10; |
| 104 | char *p; |
| 105 | mp *f, *ulmax, *xx; |
| 106 | unsigned fl = 0; |
| 107 | |
| 108 | #define f_bogus 1u |
| 109 | |
| 110 | ego(argv[0]); |
| 111 | |
| 112 | for (;;) { |
| 113 | static const struct option opt[] = { |
| 114 | { "help", 0, 0, 'h' }, |
| 115 | { "version", 0, 0, 'v' }, |
| 116 | { "usage", 0, 0, 'u' }, |
| 117 | { "radix", OPTF_ARGREQ, 0, 'r' }, |
| 118 | { 0, 0, 0, 0 } |
| 119 | }; |
| 120 | int i = mdwopt(argc, argv, "hvur:", opt, 0, 0, 0); |
| 121 | if (i < 0) |
| 122 | break; |
| 123 | switch (i) { |
| 124 | case 'h': |
| 125 | help(stdout); |
| 126 | exit(0); |
| 127 | case 'v': |
| 128 | version(stdout); |
| 129 | exit(0); |
| 130 | case 'u': |
| 131 | usage(stdout); |
| 132 | exit(0); |
| 133 | case 'r': |
| 134 | r = atoi(optarg); |
| 135 | if (r < 2 || r > 62) |
| 136 | die(EXIT_FAILURE, "bad radix `%s'", optarg); |
| 137 | break; |
| 138 | default: |
| 139 | fl |= f_bogus; |
| 140 | break; |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | if (optind + 1 != argc || (fl & f_bogus)) { |
| 145 | usage(stderr); |
| 146 | exit(EXIT_FAILURE); |
| 147 | } |
| 148 | ulmax = mp_fromulong(MP_NEW, ULONG_MAX); |
| 149 | p = argv[optind]; |
| 150 | while (isspace((unsigned char)*p)) |
| 151 | p++; |
| 152 | xx = mp_readstring(MP_NEW, argv[optind], &p, 0); |
| 153 | while (isspace((unsigned char)*p)) |
| 154 | p++; |
| 155 | if (!xx || *p || MP_CMP(xx, >, ulmax)) |
| 156 | die(EXIT_FAILURE, "bad integer `%s'", argv[optind]); |
| 157 | x = mp_toulong(xx); |
| 158 | mp_drop(xx); |
| 159 | mp_drop(ulmax); |
| 160 | f = mp_factorial(x); |
| 161 | mp_writefile(f, stdout, r); |
| 162 | fputc('\n', stdout); |
| 163 | mp_drop(f); |
| 164 | return (0); |
| 165 | } |
| 166 | |
| 167 | /*----- That's all, folks -------------------------------------------------*/ |