| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: factorial.c,v 1.2 2001/06/16 13:22:59 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 1.2 2001/06/16 13:22:59 mdw |
| 34 | * Added command-line option to select output radix. |
| 35 | * |
| 36 | * Revision 1.1 2000/07/09 21:30:49 mdw |
| 37 | * Demo program to compute factorials. |
| 38 | * |
| 39 | */ |
| 40 | |
| 41 | /*----- Header files ------------------------------------------------------*/ |
| 42 | |
| 43 | #include <stdio.h> |
| 44 | #include <stdlib.h> |
| 45 | |
| 46 | #include <mLib/mdwopt.h> |
| 47 | #include <mLib/quis.h> |
| 48 | #include <mLib/report.h> |
| 49 | |
| 50 | #include "mpmul.h" |
| 51 | |
| 52 | /*----- Main code ---------------------------------------------------------*/ |
| 53 | |
| 54 | int main(int argc, char *argv[]) |
| 55 | { |
| 56 | unsigned long x; |
| 57 | int r = 10; |
| 58 | char *p; |
| 59 | mp *f; |
| 60 | |
| 61 | ego(argv[0]); |
| 62 | |
| 63 | for (;;) { |
| 64 | static const struct option opt[] = { |
| 65 | { "radix", OPTF_ARGREQ, 0, 'r' }, |
| 66 | { 0, 0, 0, 0 } |
| 67 | }; |
| 68 | int i = mdwopt(argc, argv, "r:", opt, 0, 0, 0); |
| 69 | if (i < 0) |
| 70 | break; |
| 71 | switch (i) { |
| 72 | case 'r': |
| 73 | r = atoi(optarg); |
| 74 | if (r < 2 || r > 36) |
| 75 | die(EXIT_FAILURE, "bad radix `%s'", optarg); |
| 76 | break; |
| 77 | default: |
| 78 | exit(EXIT_FAILURE); |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | if (optind + 1 != argc) { |
| 83 | pquis(stderr, "Usage: $ [-r radix] integer\n"); |
| 84 | exit(EXIT_FAILURE); |
| 85 | } |
| 86 | x = strtoul(argv[optind], &p, 0); |
| 87 | if (*p) |
| 88 | die(EXIT_FAILURE, "bad integer `%s'", argv[optind]); |
| 89 | f = mp_factorial(x); |
| 90 | mp_writefile(f, stdout, r); |
| 91 | fputc('\n', stdout); |
| 92 | mp_drop(f); |
| 93 | return (0); |
| 94 | } |
| 95 | |
| 96 | /*----- That's all, folks -------------------------------------------------*/ |