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#include <stdio.h>
#include <stdlib.h>
#include "boolector.h"
#include "utils/btorutil.h"
int
main (int argc, char **argv)
{
int num_bits, num_bits_index, num_elements, i;
Btor *btor;
BoolectorNode **indices, *array, *ugt, *temp, *read, *formula, *max, *index;
BoolectorSort isort, esort, asort;
if (argc != 3)
{
printf ("Usage: ./max <num-bits> <num-elements>\n");
return 1;
}
num_bits = atoi (argv[1]);
if (num_bits <= 0)
{
printf ("Number of bits must be greater than zero\n");
return 1;
}
num_elements = atoi (argv[2]);
if (num_elements <= 1)
{
printf ("Number of elements must be greater than one\n");
return 1;
}
if (!btor_util_is_power_of_2 (num_elements))
{
printf ("Number of elements must be a power of two\n");
return 1;
}
num_bits_index = btor_util_log_2 (num_elements);
btor = boolector_new ();
boolector_set_opt (btor, BTOR_OPT_REWRITE_LEVEL, 0);
indices = (BoolectorNode **) malloc (sizeof (BoolectorNode *) * num_elements);
isort = boolector_bitvec_sort (btor, num_bits_index);
esort = boolector_bitvec_sort (btor, num_bits);
asort = boolector_array_sort (btor, isort, esort);
for (i = 0; i < num_elements; i++)
indices[i] = boolector_int (btor, i, isort);
array = boolector_array (btor, asort, "array");
/* current maximum is first element of array */
max = boolector_read (btor, array, indices[0]);
/* compute maximum of array */
for (i = 1; i < num_elements; i++)
{
read = boolector_read (btor, array, indices[i]);
ugt = boolector_ugt (btor, read, max);
temp = boolector_cond (btor, ugt, read, max);
boolector_release (btor, max);
max = temp;
boolector_release (btor, read);
boolector_release (btor, ugt);
}
/* show that maximum is really the maximum */
index = boolector_var (btor, isort, "index");
read = boolector_read (btor, array, index);
/* there is no arbitrary read value which is greater than the maximum */
formula = boolector_ult (btor, max, read);
boolector_dump_btor_node (btor, stdout, formula);
/* clean up */
for (i = 0; i < num_elements; i++) boolector_release (btor, indices[i]);
boolector_release (btor, formula);
boolector_release (btor, read);
boolector_release (btor, index);
boolector_release (btor, max);
boolector_release (btor, array);
boolector_release_sort (btor, isort);
boolector_release_sort (btor, esort);
boolector_release_sort (btor, asort);
boolector_delete (btor);
free (indices);
return 0;
}
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