/**********************************************************************
	A Simple Supervised Learning Utility ver 1.0

	Written by Kazuyuki HANAAHARA (hanahara@cs.kobe-u.ac.jp)

	See sample file "qa.lst"
**********************************************************************/
#include <stdio.h>
#include <stdlib.h>

/*
 *	Size parameters.
 *	Conventional DOS machine is currently assumed.(But that'll be enough)
 */
#define	BUFFSIZE	30000	/* Total buffer size */
#define	MAX_ITEM	1000	/* Maximum number of items */
#define	MAX_LENGTH	400	/* Maximum line length */
char	buff[BUFFSIZE], 	/* Buffer area for items */
	*item[MAX_ITEM][2];	/* Pointers to each Q & A */
int	Nitem;			/* Actual number of items */
int	level[MAX_ITEM];	/* A kind of difficulty of each item */

/*--------------------------------------------------------------------
	Read items from specified file pointer.

	Args.	fp	File to be read.

	Return	Number of items in the file.
*/
int ReadItem( fp )
FILE	*fp;
{
	int	n, i, l;
	char	*p;

	for( n = l = 0, item[0][0] = buff; !feof( fp ) && n < MAX_ITEM &&
		 	item[n][0] < buff + BUFFSIZE - MAX_LENGTH * 2; ){
		for( i = 0; i < 2 && !feof( fp ); ){
			/*
			 *	Get next line.
			 */
			if( fgets((p = item[n][i]), MAX_LENGTH, fp) == NULL )
				continue;
			else
				l++;
			/*
			 *	Format check.
			 */
			if( *p != 'q' && *p != 'Q' && *p != 'a' && *p != 'A' )
				continue;	/* Maybe a comment line */
			if( i == 0 && (*p != 'q' && *p != 'Q') ||
					i == 1 && (*p != 'a' && *p != 'A') ){
				printf( "** Line %d: format error **\n>>%s\n",
							l, item[n][i] );
				exit( 0 );
			}
			/*
			 *	Set next pointer. 
			 */
			while( *p != NULL && *p != '\n' )
				p++;
			*(p++) = NULL;
			if( i == 0 )
				item[n][1] = p;
			else if( n < MAX_ITEM - 1 )
				item[n+1][0] = p;
			/*
			 *	Next line...
			 */
			i++;
		}
		if( i == 2 )
			n++;	/* Read next tiem... */
	}
	if( !feof( fp ) )
		printf( "*** Warning: There are more items in the file.\n" );

	Nitem = n;
	return( n );
}

/*--------------------------------------------------------------------
	Try all items one time.

	Args.	left	Number of left items.
		try	nth try. (, 2, 3...)

	Return	Number of items not cleared.
*/
int TryItems( left, try )
int	left, try;
{
	int	n, i, j;
	char	s[100];

	printf( "***** %d items to be examined.\n", left );
	for( n = left; n > 0; n-- ){
		/*
		 *	Randomly select next item.
		 */
		i = rand() % n;
		for( j = -1; i >= 0; i-- ){
			j++;
			while( level[j] >= try )
				j++;	/* Examined(=try) or Cleared(=10000) */
		}
		/*
		 *	Display selected item for examination.
		 */
		printf( "%d:%s\n---[CR] ", j + 1, item[j][0] );
		fflush( stdin );
		getchar();
		printf( "%d:%s\n---[OK?(y/n)] ", j + 1, item[j][1] );
		fflush( stdin );
		fgets( s, 100, stdin );
		if( *s == 'y' || *s == 'Y' ){
			/*--- Judged as cleared ---*/
			level[j] = 10000;
			left--;
		}
		else{	/*--- Still not cleared ---*/
			(level[j])++;
		}
	}

	return( left );
}

/*--------------------------------------------------------------------
	Perform supervised learning
*/
void SupervisedLearn()
{
	int	n, m, i;

	/*
	 *	Reset level values.
	 */
	for( n = 0; n < Nitem; n++ )
		level[n] = 0;
	/*
	 *	Try all items until they all are cleared.
	 */
	for( i = 1; n > 0; i++ ){
		m = TryItems( n, i );
		/* Display result. */
		printf( "\n***** Try %d:%5.1lf%%(%d/%d)\n\n",
			i, (double)(n-m)/(double)n * 100.0, n - m, n );
		n = m;
	}
}

int main( argc, argv )
int	argc;
char	*argv[];
{
	FILE	*fp;
	int	n, i;

	if( argc == 1 ){
		printf( "sl [Q/A list file: see 'qa.lst']\n" );
		exit( 0 );
	}
	if( (fp = fopen( argv[1], "r" )) == NULL ){
		printf( "File `%s' not found.\n", argv[1] );
		exit( 0 );
	}
	ReadItem( fp );
	printf( "[[[ There are %d items in `%s']]]\n", Nitem, argv[1] );
	fclose( fp );
	srand( time( NULL ) );
	SupervisedLearn();
}