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/* -*- mode: C -*- */
/*
IGraph library.
Copyright (C) 2007-2012 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>
int print_mincut(const igraph_t *graph, igraph_real_t value,
const igraph_vector_t *partition,
const igraph_vector_t *partition2,
const igraph_vector_t *cut,
const igraph_vector_t *capacity) {
long int i, nc=igraph_vector_size(cut);
igraph_bool_t directed=igraph_is_directed(graph);
printf("mincut value: %g\n", (double) value);
printf("first partition: "); igraph_vector_print(partition);
printf("second partition: "); igraph_vector_print(partition2);
printf("edges in the cut: ");
for (i=0; i<nc; i++) {
long int edge=VECTOR(*cut)[i];
long int from=IGRAPH_FROM(graph, edge);
long int to =IGRAPH_TO (graph, edge);
if (!directed && from > to) {
igraph_integer_t tmp=from;
from=to;
to=tmp;
}
printf("%li-%li (%g), ", from, to, VECTOR(*capacity)[edge]);
}
printf("\n");
return 0;
}
int main() {
igraph_t g;
igraph_vector_t weights, partition, partition2, cut;
igraph_real_t value;
igraph_vector_init(&partition, 0);
igraph_vector_init(&partition2, 0);
igraph_vector_init(&cut, 0);
/* -------------------------------------------- */
igraph_small(&g, 0, IGRAPH_UNDIRECTED,
0,1, 0,4, 1,2, 1,4, 1,5, 2,3, 2,6, 3,6, 3,7, 4,5, 5,6, 6,7,
-1);
igraph_vector_init_int_end(&weights, -1, 2,3,3,2,2, 4,2,2,2,3, 1,3, -1);
igraph_mincut(&g, &value, &partition, &partition2, &cut, &weights);
print_mincut(&g, value, &partition, &partition2, &cut, &weights);
igraph_vector_destroy(&weights);
igraph_destroy(&g);
/* -------------------------------------------- */
igraph_small(&g, 6, IGRAPH_DIRECTED,
0,1,1,2,2,3, 0,5,5,4,4,3, 3,0, -1);
igraph_vector_init_int_end(&weights, -1, 3,1,2, 10,1,3, 2, -1);
igraph_mincut(&g, &value, &partition, &partition2, &cut, &weights);
print_mincut(&g, value, &partition, &partition2, &cut, &weights);
igraph_vector_destroy(&weights);
igraph_destroy(&g);
/* -------------------------------------------- */
igraph_small(&g, 5, IGRAPH_DIRECTED,
4,3, 3,2, 2,1, 1,0,
-1);
igraph_vector_init_int_end(&weights, -1, 1,1,1,1, -1);
igraph_mincut(&g, &value, &partition, &partition2, &cut, &weights);
print_mincut(&g, value, &partition, &partition2, &cut, &weights);
igraph_vector_destroy(&weights);
igraph_destroy(&g);
/* -------------------------------------------- */
igraph_vector_destroy(&cut);
igraph_vector_destroy(&partition2);
igraph_vector_destroy(&partition);
return 0;
}
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