/************************************************************
;                                                           *
;  William M. Spears					    *
;  Navy Center for Applied Research in AI                   *
;  Naval Research Laboratory                                *
;                                                           *
;  This software is the property of the Department of the   *
;  Navy. Permission is hereby granted to copy all or any    *
;  part of this program for free distribution, however      *
;  this header is required on all copies.		    *
;                                                           *
; File: utility.c                                           *
;************************************************************/

#include "header.h"

/* Keep track of the generation number...*/

void time_keeper ()
{
   gen_time++;
   printf("\nIteration %d, Generation %d, Evaluations %d: \n",
	  iteration, gen_time, evals);
}

/* Return a random integer from low to high */

short rrandom (low, high)
short low, high;
{
	long random();
	short nb = high - low + 1;
	return(random() % nb + low);
}

/* Return a random integer from 1 to n inclusive.*/

int myrand (n)
int n;
{  
   short rrandom();

   return(rrandom(1, n));
}

/* Return a random real from (0.0 1.0).*/

double ssrand ()
{
   short rrandom();

   return((double)(1 + rrandom(1, 31998)) / 32000.0);
}

/* Return a random bit (0 or 1).*/

int brand ()
{ 
   short rrandom();

   return(rrandom(0, 1));
}

/********************************************************/

/* Display individual i. */

void show_individual (i)
{
   int j;

   for (j = 1; j <= length; j++) printf("%d", c[i][j]);
   printf("\n");
}

/* Display whole population. */

void show_pop ()
{
   int i;

   for (i = 1; i <= size; i++) {
     printf("Individual %d: ", i);
     show_individual(i);
   }
}

/* Display best individual seen so far. */

void show_best_individual ()
{
   int i;

   for (i = 1; i <= length; i++) printf("%d", b[i]);
}

/* Print best individual in a file. */

void fshow_best_individual (fp)
FILE *fp;
{
   int i;

   for (i = 1; i <= length; i++) fprintf(fp, "%d", b[i]);
}

/********************************************************/
 
/* Swap takes as input pointers to 2 elements and swaps them. */

swap_elements(x,y)	/* Interchange two elements */
int *x,*y;
{
	int temp;
	temp = *x;
	*x = *y;
	*y = temp;
}

/* Selectsort takes as input an array and its size and performs a
   selection sort on this array. */

selectsort(n, a)	/* Perform a selectsort */
int n, a[];
{
	register int small, j, k;
	for(k = 0; k < n - 1;k++)
	{
		small = k;
		for(j = k + 1; j < n; j++)
		{
		                                /* Select the smallest */
			if (a[j] < a[small])	/* from among a[k],...,a[n-1]*/
			small = j;		/* and swap with a[k]. */
		}
		swap_elements(&a[k],&a[small]);
}	}