/*************************************************************************//*									 *//*	Program to prepare data file for cross-validation		 *//*	-------------------------------------------------		 *//*									 *//*	The number of blocks for the cross-validation appears as the	 *//*	first argument.  The data are shuffled and divided into the	 *//*	specified number of blocks, with class distributions as even	 *//*	as possible in each block.					 *//*									 *//*************************************************************************/#include <math.h>#include <stdio.h>long	random();#define	randf			((random()&2147483647) / 2147483648.0)#define	ForEach(var,F,L)	for(var=F; var<=L; ++var) #define	dig(x)			(x >= '0' && x <= '9')#define MAXLINE 5000		/* maximum line length */char	**Item;int	ItemSpace=1000, MaxItem=0;    main(argc, argv)/*  ----  */    int argc;    char *argv[];{    int i, First=0, Last, Length, Splits;    char Line[MAXLINE], **ClassPtr, *Temp, *BeginClass();    sscanf(argv[1], "%d", &Splits);    Item = (char **) malloc(ItemSpace * sizeof(char *));    while ( fgets(Line, MAXLINE, stdin) )    {	if ( MaxItem >= ItemSpace )	{	    ItemSpace += 1000;	    Item = (char **) realloc(Item, ItemSpace * sizeof(char *));	}	Length = strlen(Line)+2;	Item[MaxItem] = (char *) malloc(Length);	memcpy(Item[MaxItem], Line, Length);	MaxItem++;    }    if ( ! MaxItem-- ) exit(1);    Shuffle();    /*  Find classes  */    ClassPtr = (char **) malloc((MaxItem+1) * sizeof(char *));    ForEach(i, 0, MaxItem)    {	ClassPtr[i] = BeginClass(Item[i]);    }    /*  Sort by class  */    fprintf(stderr, "\nClass frequencies:\n");    while ( First <= MaxItem )    {	Last = First;	ForEach(i, First+1, MaxItem)	{	    if ( ! strcmp(ClassPtr[i], ClassPtr[First]) )	    {		Last++;		Temp = Item[Last];		Item[Last] = Item[i];		Item[i] = Temp;		Temp = ClassPtr[Last];		ClassPtr[Last] = ClassPtr[i];		ClassPtr[i] = Temp;	    }	}	fprintf(stderr, "%6d class %s\n", Last-First+1, ClassPtr[First]);	First = Last+1;    }    ForEach(First, 0, Splits-1)    {	for ( i = First ; i <= MaxItem ; i += Splits )	{	    printf("%s\n", Item[i]);	}    }}/*************************************************************************//*									 *//*	Find the beginning character of a class name			 *//*									 *//*************************************************************************/char *BeginClass(S)/*    ----------  */    char *S;{    char *F;    F = S - 1;    do    {	S = F + 1;	while ( *S == ' ' || *S == '\t' || *S == '\n' ) S++;	F = S;	while ( *F != ',' && (*F != '.' || dig(*(F+1))) && *F != '\n' ) F++;    } while ( *F == ',' );    if ( *F != '.' ) *F = '.';    *(F+1) = '\0';    return S;}/*************************************************************************//*									 *//*	Shuffle the data items						 *//*									 *//*************************************************************************/    Shuffle()/*  -------  */{    int this, alt, left = MaxItem+1;    char *hold;    this = 0;    while ( left )    {        alt = this + (left--) * randf;	if ( alt > MaxItem || alt < this )	{	    fprintf(stderr, "ERROR!\n");	    exit(1);	}        hold = Item[this];        Item[this++] = Item[alt];        Item[alt] = hold;    }}