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/* -*- mode: C -*- */
/*
IGraph library.
Copyright (C) 2010-2012 Gabor Csardi <csardi.gabor@gmail.com>
334 Harvard st, Cambridge MA, 02139 USA
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include <igraph.h>
#define NODES 1000
#define CLIQUE_SIZE 10
#define NO_CLIQUES 10
#define INT(a) (igraph_rng_get_integer(igraph_rng_default(), 0, (a)))
int permutation(igraph_vector_t *vec) {
int i, r, tmp;
for (i=0; i<CLIQUE_SIZE; i++) {
r=INT(NODES-1);
tmp=VECTOR(*vec)[i];
VECTOR(*vec)[i]=VECTOR(*vec)[r];
VECTOR(*vec)[r]=tmp;
}
return 0;
}
int sort_cmp(const void *a, const void *b) {
const igraph_vector_t **da = (const igraph_vector_t **) a;
const igraph_vector_t **db = (const igraph_vector_t **) b;
int i, alen=igraph_vector_size(*da), blen=igraph_vector_size(*db);
if (alen != blen) { return (alen < blen) - (alen > blen); }
for (i=0; i<alen; i++) {
int ea=VECTOR(**da)[i], eb=VECTOR(**db)[i];
if (ea != eb) { return (ea > eb) - (ea < eb); }
}
return 0;
}
void sort_cliques(igraph_vector_ptr_t *cliques) {
int i, n=igraph_vector_ptr_size(cliques);
for (i=0; i<n; i++) {
igraph_vector_t *v=VECTOR(*cliques)[i];
igraph_vector_sort(v);
}
igraph_qsort(VECTOR(*cliques), (size_t) n,
sizeof(igraph_vector_t *), sort_cmp);
}
void print_and_destroy_cliques(igraph_vector_ptr_t *cliques) {
int i;
sort_cliques(cliques);
for (i=0; i<igraph_vector_ptr_size(cliques); i++) {
igraph_vector_t *v=VECTOR(*cliques)[i];
igraph_vector_print(v);
igraph_vector_destroy(v);
igraph_free(v);
}
}
int main() {
igraph_t g, g2, cli;
igraph_vector_t perm;
igraph_vector_ptr_t cliques;
igraph_integer_t no;
int i;
igraph_rng_seed(igraph_rng_default(), 42);
/* Create a graph that has a random component, plus a number of
relatively small cliques */
igraph_vector_init_seq(&perm, 0, NODES-1);
igraph_erdos_renyi_game(&g, IGRAPH_ERDOS_RENYI_GNM, NODES, NODES,
/*directed=*/ 0, /*loops=*/ 0);
igraph_full(&cli, CLIQUE_SIZE, /*directed=*/ 0, /*loops=*/ 0);
for (i=0; i<NO_CLIQUES; i++) {
/* Permute vertices of g */
permutation(&perm);
igraph_permute_vertices(&g, &g2, &perm);
igraph_destroy(&g);
g=g2;
/* Add a clique */
igraph_union(&g2, &g, &cli, /*edge_map1=*/ 0, /*edge_map2=*/ 0);
igraph_destroy(&g);
g=g2;
}
igraph_simplify(&g, /*multiple=*/ 1, /*loop=*/ 0, /*edge_comb=*/ 0);
igraph_vector_destroy(&perm);
igraph_destroy(&cli);
/* Find the maximal cliques */
igraph_vector_ptr_init(&cliques, 0);
igraph_maximal_cliques(&g, &cliques, /*min_size=*/ 3,
/*max_size=*/ 0 /*no limit*/);
igraph_maximal_cliques_count(&g, &no, /*min_size=*/ 3,
/*max_size=*/ 0 /*no limit*/);
if (no != igraph_vector_ptr_size(&cliques)) { return 1; }
/* Print and destroy them */
print_and_destroy_cliques(&cliques);
/* Clean up */
igraph_vector_ptr_destroy(&cliques);
igraph_destroy(&g);
/* Build a triangle with a loop (thanks to Emmanuel Navarro) */
igraph_small(&g, 3, IGRAPH_UNDIRECTED, 0, 1, 1, 2, 2, 0, 0, 0, -1);
/* Find the maximal cliques */
igraph_vector_ptr_init(&cliques, 0);
igraph_maximal_cliques(&g, &cliques, /*min_size=*/ 3,
/*max_size=*/ 0 /*no limit*/);
igraph_maximal_cliques_count(&g, &no, /*min_size=*/ 3,
/*max_size=*/ 0 /*no limit*/);
if (no != igraph_vector_ptr_size(&cliques)) { return 2; }
/* Print and destroy them */
print_and_destroy_cliques(&cliques);
/* Clean up */
igraph_vector_ptr_destroy(&cliques);
igraph_destroy(&g);
return 0;
}
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