1 /**

     2  * test/demos/clplaner.c

     3  * Copyright (C) 2008 Markus Broeker

     4  */

     5 

     6 #include <stdio.h>

     7 #include <stdlib.h>

     8 #include <string.h>

     9 #include <time.h>

    10 #include <limits.h>

    11 

    12 #define MAXLOOP 25

    13 #define MAXLINE 80

    14 

    15 #ifndef MAXTEAM

    16 #define MAXTEAM 32

    17 #endif

    18 

    19 #define getrandom(max) (1+(int)((float)(max)*rand()/RAND_MAX))

    20 

    21 void swap (int *v, int i, int j)

    22 {

    23     int temp;

    24 

    25     if (i == j)

    26         return;

    27 

    28     temp = v[i];

    29 

    30     v[i] = v[j];

    31     v[j] = temp;

    32 }

    33 

    34 void cleanup (char **first, char **second)

    35 {

    36     int i;

    37 

    38     i = 0;

    39     while (first[i] != NULL)

    40         free (first[i++]);

    41 

    42     i = 0;

    43     while (second[i] != NULL)

    44         free (second[i++]);

    45 }

    46 

    47 unsigned int time_seed ()

    48 {

    49     time_t now = time (NULL);

    50 

    51     unsigned char *p = (unsigned char *)&now;

    52     unsigned int seed = 0;

    53 

    54     size_t i;

    55 

    56     for (i = 0; i < sizeof (now); i++)

    57         seed = seed * (UCHAR_MAX + 2U) + p[i];

    58 

    59     return seed;

    60 }

    61 

    62 int getTeams (FILE * f, char **first, int *first_idx, char **second, int *second_idx)

    63 {

    64     int i;

    65     char buffer[MAXLINE + 1];

    66     char *ptr;

    67 

    68     i = 0;

    69     while ((i < MAXTEAM) && fgets (buffer, MAXLINE, f) != NULL) {

    70         if ((first[i] = malloc (MAXLINE + 1)) == NULL) {

    71             perror ("malloc");

    72             break;

    73         }

    74         if ((ptr = strchr (buffer, '\n')))

    75             *ptr = '\0';

    76 

    77         strncpy (first[i], buffer, MAXLINE);

    78         first_idx[i] = i;

    79 

    80         if (fgets (buffer, MAXLINE, f) == NULL) {

    81             printf ("You need 2, 4, 6, ..., or %d teams in your file\n", 2 * MAXTEAM);

    82             second[i] = first[i + 1] = NULL;

    83             cleanup (first, second);

    84             fclose (f);

    85             exit (EXIT_FAILURE);

    86         }

    87 

    88         if ((second[i] = malloc (MAXLINE + 1)) == NULL) {

    89             perror ("malloc");

    90             break;

    91         }

    92         if ((ptr = strchr (buffer, '\n')))

    93             *ptr = '\0';

    94 

    95         strncpy (second[i], buffer, MAXLINE);

    96         second_idx[i] = i;

    97         i++;

    98     }

    99 

   100     first[i] = second[i] = NULL;

   101 

   102     return i;

   103 }

   104 

   105 void shakeTeamIdx (int *first_idx, int *second_idx, int teams)

   106 {

   107     int i, j, k;

   108 

   109     /*

   110      * swap the index MAXLOOP times...

   111      */

   112     for (i = 0; i < MAXLOOP; i++) {

   113         for (j = 0; j < teams; j++) {

   114             k = getrandom (teams - 1);

   115             swap (second_idx, j, k);

   116 

   117             k = getrandom (teams - 1);

   118             swap (first_idx, j, k);

   119         }

   120     }

   121 

   122     /*

   123      * avoid group clashes

   124      */

   125     for (i = 0; i < teams - 1; i++) {

   126         if (first_idx[i] == second_idx[i])

   127             swap (first_idx, i, i + 1);

   128     }

   129 

   130     if (first_idx[i] == second_idx[i])

   131         swap (first_idx, i, i - 1);

   132 }

   133 

   134 int main (int argc, char **argv)

   135 {

   136     FILE *f;

   137 

   138     char *first[MAXTEAM + 1];

   139     char *second[MAXTEAM + 1];

   140 

   141     int first_idx[MAXTEAM];

   142     int second_idx[MAXTEAM];

   143 

   144     int i, teams;

   145 

   146     if (argc != 2) {

   147         printf ("Usage: %s FILE\n\n", argv[0]);

   148         printf ("One Team per line, seperated by newline, n=2, 4, ..., or %d\n", 2 * MAXTEAM);

   149         printf ("Team n is the Groupwinner, n+1 is the Runners Up\n");

   150         printf ("Report bugs to mbroeker@largo.homelinux.org\n");

   151         return EXIT_FAILURE;

   152     }

   153 

   154     if ((f = fopen (argv[1], "r")) == NULL) {

   155         perror ("fopen");

   156         return EXIT_FAILURE;

   157     }

   158 

   159     srand (time_seed ());

   160 

   161     teams = getTeams (f, first, first_idx, second, second_idx);

   162     shakeTeamIdx (first_idx, second_idx, teams);

   163 

   164     for (i = 0; i < teams; i++)

   165         printf ("%30s vs %s\n", second[second_idx[i]], first[first_idx[i]]);

   166 

   167     cleanup (first, second);

   168 

   169     if (f != NULL)

   170         fclose (f);

   171 

   172     return EXIT_SUCCESS;

   173 }