path: root/hack/hack.invent.c

/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
/* hack.invent.c - version 1.0.3 */
/* $FreeBSD: src/games/hack/hack.invent.c,v 1.4 1999/11/16 10:26:36 marcel Exp $ */

#include "hack.h"
extern struct obj zeroobj;
extern char quitchars[];

static void		 assigninvlet(struct obj *);
static struct obj	*mkgoldobj(long);
static bool		 ckunpaid(struct obj *);
static char		 obj_to_let(struct obj *);
static char		*xprname(struct obj *, char);
static void		 doinv(char *);
static bool		 merged(struct obj *, struct obj *, bool);
static bool		 countgold(void);

#ifndef NOWORM
extern struct wseg *wsegs[32];
#endif /* NOWORM */

#define	NOINVSYM	'#'

static int lastinvnr = 51;	/* 0 ... 51 */

static void
assigninvlet(struct obj *otmp)
{
	boolean inuse[52];
	int i;
	struct obj *obj;

	for (i = 0; i < 52; i++)
		inuse[i] = FALSE;
	for (obj = invent; obj; obj = obj->nobj)
		if (obj != otmp) {
			i = obj->invlet;
			if ('a' <= i && i <= 'z')
				inuse[i - 'a'] = TRUE;
			else if ('A' <= i && i <= 'Z')
				inuse[i - 'A' + 26] = TRUE;
			if (i == otmp->invlet)
				otmp->invlet = 0;
		}
	if ((i = otmp->invlet) &&
	    (('a' <= i && i <= 'z') || ('A' <= i && i <= 'Z')))
		return;
	for (i = lastinvnr + 1; i != lastinvnr; i++) {
		if (i == 52) {
			i = -1;
			continue;
		}
		if (!inuse[i])
			break;
	}
	otmp->invlet = (inuse[i] ? NOINVSYM :
			(i < 26) ? ('a' + i) : ('A' + i - 26));
	lastinvnr = i;
}

struct obj *
addinv(struct obj *obj)
{
	struct obj *otmp;

	/* merge or attach to end of chain */
	if (!invent) {
		invent = obj;
		otmp = NULL;
	} else
		for (otmp = invent; /* otmp */; otmp = otmp->nobj) {
			if (merged(otmp, obj, 0))
				return (otmp);
			if (!otmp->nobj) {
				otmp->nobj = obj;
				break;
			}
		}
	obj->nobj = 0;

	if (flags.invlet_constant) {
		assigninvlet(obj);
		/*
		 * The ordering of the chain is nowhere significant
		 * so in case you prefer some other order than the
		 * historical one, change the code below.
		 */
		if (otmp) {	/* find proper place in chain */
			otmp->nobj = 0;
			if ((invent->invlet ^ 040) > (obj->invlet ^ 040)) {
				obj->nobj = invent;
				invent = obj;
			} else
				for (otmp = invent;; otmp = otmp->nobj) {
					if (!otmp->nobj ||
					    (otmp->nobj->invlet ^ 040) >
					    (obj->invlet ^ 040)) {
						obj->nobj = otmp->nobj;
						otmp->nobj = obj;
						break;
					}
				}
		}
	}

	return (obj);
}

void
useup(struct obj *obj)
{
	if (obj->quan > 1) {
		obj->quan--;
		obj->owt = weight(obj);
	} else {
		setnotworn(obj);
		freeinv(obj);
		obfree(obj, NULL);
	}
}

void
freeinv(struct obj *obj)
{
	struct obj *otmp;

	if (obj == invent)
		invent = invent->nobj;
	else {
		for (otmp = invent; otmp->nobj != obj; otmp = otmp->nobj)
			if (!otmp->nobj)
				panic("freeinv");
		otmp->nobj = obj->nobj;
	}
}

/* destroy object in fobj chain (if unpaid, it remains on the bill) */
void
delobj(struct obj *obj)
{
	freeobj(obj);
	unpobj(obj);
	obfree(obj, NULL);
}

/* unlink obj from chain starting with fobj */
void
freeobj(struct obj *obj)
{
	struct obj *otmp;

	if (obj == fobj)
		fobj = fobj->nobj;
	else {
		for (otmp = fobj; otmp->nobj != obj; otmp = otmp->nobj)
			if (!otmp)
				panic("error in freeobj");
		otmp->nobj = obj->nobj;
	}
}

/* Note: freegold throws away its argument! */
void
freegold(struct gold *gold)
{
	struct gold *gtmp;

	if (gold == fgold)
		fgold = gold->ngold;
	else {
		for (gtmp = fgold; gtmp->ngold != gold; gtmp = gtmp->ngold)
			if (!gtmp)
				panic("error in freegold");
		gtmp->ngold = gold->ngold;
	}
	free(gold);
}

void
deltrap(struct trap *trap)
{
	struct trap *ttmp;

	if (trap == ftrap)
		ftrap = ftrap->ntrap;
	else {
		for (ttmp = ftrap; ttmp->ntrap != trap; ttmp = ttmp->ntrap)
			; /* nothing */
		ttmp->ntrap = trap->ntrap;
	}
	free(trap);
}

struct wseg *m_atseg;

struct monst *
m_at(int x, int y)
{
	struct monst *mtmp;
#ifndef NOWORM
	struct wseg *wtmp;
#endif /* NOWORM */

	m_atseg = NULL;
	for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
		if (mtmp->mx == x && mtmp->my == y)
			return (mtmp);
#ifndef NOWORM
		if (mtmp->wormno) {
			for (wtmp = wsegs[mtmp->wormno]; wtmp; wtmp = wtmp->nseg)
				if (wtmp->wx == x && wtmp->wy == y) {
					m_atseg = wtmp;
					return (mtmp);
				}
		}

#endif /* NOWORM */
	}
	return (0);
}

struct obj *
o_at(int x, int y)
{
	struct obj *otmp;

	for (otmp = fobj; otmp; otmp = otmp->nobj)
		if (otmp->ox == x && otmp->oy == y)
			return (otmp);
	return (0);
}

struct obj *
sobj_at(int n, int x, int y)
{
	struct obj *otmp;

	for (otmp = fobj; otmp; otmp = otmp->nobj)
		if (otmp->ox == x && otmp->oy == y && otmp->otyp == n)
			return (otmp);
	return (0);
}

bool
carried(struct obj *obj)
{
	struct obj *otmp;

	for (otmp = invent; otmp; otmp = otmp->nobj)
		if (otmp == obj)
			return (1);
	return (0);
}

bool
carrying(int type)
{
	struct obj *otmp;

	for (otmp = invent; otmp; otmp = otmp->nobj)
		if (otmp->otyp == type)
			return (TRUE);
	return (FALSE);
}

struct obj *
o_on(unsigned int id, struct obj *objchn)
{
	while (objchn) {
		if (objchn->o_id == id)
			return (objchn);
		objchn = objchn->nobj;
	}
	return (NULL);
}

struct trap *
t_at(int x, int y)
{
	struct trap *trap = ftrap;

	while (trap) {
		if (trap->tx == x && trap->ty == y)
			return (trap);
		trap = trap->ntrap;
	}
	return (0);
}

struct gold *
g_at(int x, int y)
{
	struct gold *gold = fgold;

	while (gold) {
		if (gold->gx == x && gold->gy == y)
			return (gold);
		gold = gold->ngold;
	}
	return (0);
}

/* make dummy object structure containing gold - for temporary use only */
static struct obj *
mkgoldobj(long q)
{
	struct obj *otmp;

	otmp = newobj(0);
	/* should set o_id etc. but otmp will be freed soon */
	otmp->olet = '$';
	u.ugold -= q;
	OGOLD(otmp) = q;
	flags.botl = 1;
	return (otmp);
}

/*
 * getobj returns:
 *	struct obj *xxx:	object to do something with.
 *	NULL			error return: no object.
 *	&zeroobj		explicitly no object (as in w-).
 */
struct obj *
getobj(const char *let, const char *word)
{
	struct obj *otmp;
	char ilet, ilet1, ilet2;
	char buf[BUFSZ];
	char lets[BUFSZ];
	int foo = 0, foo2;
	char *bp = buf;
	xchar allowcnt = 0;	/* 0, 1 or 2 */
	boolean allowgold = FALSE;
	boolean allowall = FALSE;
	boolean allownone = FALSE;
	xchar foox = 0;
	long cnt;

	if (*let == '0')
		let++, allowcnt = 1;
	if (*let == '$')
		let++, allowgold = TRUE;
	if (*let == '#')
		let++, allowall = TRUE;
	if (*let == '-')
		let++, allownone = TRUE;
	if (allownone)
		*bp++ = '-';
	if (allowgold)
		*bp++ = '$';
	if (bp > buf && bp[-1] == '-')
		*bp++ = ' ';

	ilet = 'a';
	for (otmp = invent; otmp; otmp = otmp->nobj) {
		if (!*let || strchr(let, otmp->olet)) {
			bp[foo++] = flags.invlet_constant ? otmp->invlet : ilet;

			/* ugly check: remove inappropriate things */
			if ((!strcmp(word, "take off") &&
			     !(otmp->owornmask & (W_ARMOR - W_ARM2)))
			    || (!strcmp(word, "wear") &&
				(otmp->owornmask & (W_ARMOR | W_RING)))
			    || (!strcmp(word, "wield") &&
				(otmp->owornmask & W_WEP))) {
				foo--;
				foox++;
			}
		}
		if (ilet == 'z')
			ilet = 'A';
		else
			ilet++;
	}
	bp[foo] = 0;
	if (foo == 0 && bp > buf && bp[-1] == ' ')
		*--bp = 0;
	strcpy(lets, bp);	/* necessary since we destroy buf */
	if (foo > 5) {		/* compactify string */
		foo = foo2 = 1;
		ilet2 = bp[0];
		ilet1 = bp[1];
		while ((ilet = bp[++foo2] = bp[++foo])) {
			if (ilet == ilet1 + 1) {
				if (ilet1 == ilet2 + 1)
					bp[foo2 - 1] = ilet1 = '-';
				else if (ilet2 == '-') {
					bp[--foo2] = ++ilet1;
					continue;
				}
			}
			ilet2 = ilet1;
			ilet1 = ilet;
		}
	}
	if (!foo && !allowall && !allowgold && !allownone) {
		pline("You don't have anything %sto %s.",
		      foox ? "else " : "", word);
		return (0);
	}
	for (;;) {
		if (!buf[0])
			pline("What do you want to %s [*]? ", word);
		else
			pline("What do you want to %s [%s or ?*]? ",
			      word, buf);

		cnt = 0;
		ilet = readchar();
		while (digit(ilet) && allowcnt) {
			if (cnt < 100000000)
				cnt = 10 * cnt + (ilet - '0');
			else
				cnt = 999999999;
			allowcnt = 2;	/* signal presence of cnt */
			ilet = readchar();
		}
		if (digit(ilet)) {
			pline("No count allowed with this command.");
			continue;
		}
		if (strchr(quitchars, ilet))
			return (NULL);
		if (ilet == '-')
			return (allownone ? &zeroobj : NULL);
		if (ilet == '$') {
			if (!allowgold) {
				pline("You cannot %s gold.", word);
				continue;
			}
			if (!(allowcnt == 2 && cnt < u.ugold))
				cnt = u.ugold;
			return (mkgoldobj(cnt));
		}
		if (ilet == '?') {
			doinv(lets);
			if (!(ilet = morc))
				continue;
			/* he typed a letter (not a space) to more() */
		} else if (ilet == '*') {
			doinv(NULL);
			if (!(ilet = morc))
				continue;
			/* ... */
		}
		if (flags.invlet_constant) {
			for (otmp = invent; otmp; otmp = otmp->nobj)
				if (otmp->invlet == ilet)
					break;
		} else {
			if (ilet >= 'A' && ilet <= 'Z')
				ilet += 'z' - 'A' + 1;
			ilet -= 'a';
			for (otmp = invent; otmp && ilet;
			     ilet--, otmp = otmp->nobj)
				; /* nothing */
		}
		if (!otmp) {
			pline("You don't have that object.");
			continue;
		}
		if (cnt < 0 || otmp->quan < cnt) {
			pline("You don't have that many! [You have %u]" ,
			    otmp->quan);
			continue;
		}
		break;
	}
	if (!allowall && let && !strchr(let, otmp->olet)) {
		pline("That is a silly thing to %s.", word);
		return (0);
	}
	if (allowcnt == 2) {	/* cnt given */
		if (cnt == 0)
			return (0);
		if (cnt != otmp->quan) {
			struct obj *obj;
			obj = splitobj(otmp, (int)cnt);
			if (otmp == uwep)
				setuwep(obj);
		}
	}
	return (otmp);
}

static bool
ckunpaid(struct obj *otmp)
{
	return (otmp->unpaid);
}

/* interactive version of getobj - used for Drop and Identify */
/* return the number of times fn was called successfully */
int
ggetobj(const char *word, int (*fn)(struct obj *), int max)
{
	char buf[BUFSZ];
	char *ip;
	char sym;
	int oletct = 0, iletct = 0;
	boolean allflag = FALSE;
	char olets[20], ilets[20];
	bool (*ckfn)(struct obj *) = (bool (*)()) 0;
	xchar allowgold = (u.ugold && !strcmp(word, "drop")) ? 1 : 0; /* BAH */

	if (!invent && !allowgold) {
		pline("You have nothing to %s.", word);
		return (0);
	} else {
		struct obj *otmp = invent;
		int uflg = 0;

		if (allowgold)
			ilets[iletct++] = '$';
		ilets[iletct] = 0;
		while (otmp) {
			if (!strchr(ilets, otmp->olet)) {
				ilets[iletct++] = otmp->olet;
				ilets[iletct] = 0;
			}
			if (otmp->unpaid)
				uflg = 1;
			otmp = otmp->nobj;
		}
		ilets[iletct++] = ' ';
		if (uflg)
			ilets[iletct++] = 'u';
		if (invent)
			ilets[iletct++] = 'a';
		ilets[iletct] = 0;
	}
	pline("What kinds of thing do you want to %s? [%s] ",
	      word, ilets);
	getlin(buf);
	if (buf[0] == '\033') {
		clrlin();
		return (0);
	}
	ip = buf;
	olets[0] = 0;
	while ((sym = *ip++)) {
		if (sym == ' ')
			continue;
		if (sym == '$') {
			if (allowgold == 1)
				(*fn)(mkgoldobj(u.ugold));
			else if (!u.ugold)
				pline("You have no gold.");
			allowgold = 2;
		} else if (sym == 'a' || sym == 'A')
			allflag = TRUE;
		else if (sym == 'u' || sym == 'U')
			ckfn = ckunpaid;
		else if (strchr("!%?[()=*/\"0", sym)) {
			if (!strchr(olets, sym)) {
				olets[oletct++] = sym;
				olets[oletct] = 0;
			}
		} else
			pline("You don't have any %c's.", sym);
	}
	if (allowgold == 2 && !oletct)
		return (1);	/* he dropped gold (or at least tried to) */
	else
		return (askchain(invent, olets, allflag, fn, ckfn, max));
}

/*
 * Walk through the chain starting at objchn and ask for all objects
 * with olet in olets (if nonNULL) and satisfying ckfn (if nonNULL)
 * whether the action in question (i.e., fn) has to be performed.
 * If allflag then no questions are asked. Max gives the max nr of
 * objects to be treated. Return the number of objects treated.
 */
int
askchain(struct obj *objchn, char *olets, int allflag,
	int (*fn)(struct obj *), bool (*ckfn)(struct obj *), int max)
{
	struct obj *otmp, *otmp2;
	char sym, ilet;
	int cnt = 0;

	ilet = 'a' - 1;
	for (otmp = objchn; otmp; otmp = otmp2) {
		if (ilet == 'z')
			ilet = 'A';
		else
			ilet++;
		otmp2 = otmp->nobj;
		if (olets && *olets && !strchr(olets, otmp->olet))
			continue;
		if (ckfn && !(*ckfn)(otmp))
			continue;
		if (!allflag) {
			pline("%s", xprname(otmp, ilet));
			addtopl(" [nyaq]? ");
			sym = readchar();
		} else
			sym = 'y';

		switch (sym) {
		case 'a':
			allflag = 1;
		case 'y':
			cnt += (*fn)(otmp);
			if (--max == 0)
				goto ret;
		case 'n':
		default:
			break;
		case 'q':
			goto ret;
		}
	}
	pline(cnt ? "That was all." : "No applicable objects.");
ret:
	return (cnt);
}

/* should of course only be called for things in invent */
static char
obj_to_let(struct obj *obj)
{
	struct obj *otmp;
	char ilet;

	if (flags.invlet_constant)
		return (obj->invlet);
	ilet = 'a';
	for (otmp = invent; otmp && otmp != obj; otmp = otmp->nobj)
		if (++ilet > 'z')
			ilet = 'A';
	return (otmp ? ilet : NOINVSYM);
}

void
prinv(struct obj *obj)
{
	pline("%s", xprname(obj, obj_to_let(obj)));
}

static char *
xprname(struct obj *obj, char let)
{
	static char li[BUFSZ];

	sprintf(li, "%c - %s.",
		flags.invlet_constant ? obj->invlet : let,
		doname(obj));
	return (li);
}

int
ddoinv(void)
{
	doinv(NULL);
	return (0);
}

/* called with 0 or "": all objects in inventory */
/* otherwise: all objects with (serial) letter in lets */
static void
doinv(char *lets)
{
	struct obj *otmp;
	char ilet;
	int ct = 0;
	char any[BUFSZ];

	morc = 0;		/* just to be sure */
	if (!invent) {
		pline("Not carrying anything.");
		return;
	}

	cornline(0, NULL);
	ilet = 'a';
	for (otmp = invent; otmp; otmp = otmp->nobj) {
		if (flags.invlet_constant)
			ilet = otmp->invlet;
		if (!lets || !*lets || strchr(lets, ilet)) {
			cornline(1, xprname(otmp, ilet));
			any[ct++] = ilet;
		}
		if (!flags.invlet_constant)
			if (++ilet > 'z')
				ilet = 'A';
	}
	any[ct] = 0;
	cornline(2, any);
}

int
dotypeinv(void)				/* free after Robert Viduya */
{
	/* Changed to one type only, so he doesnt have to type cr */
	char c, ilet;
	char stuff[BUFSZ];
	int stct;
	struct obj *otmp;
	boolean billx = inshop() && doinvbill(0);
	boolean unpd = FALSE;

	if (!invent && !u.ugold && !billx) {
		pline("You aren't carrying anything.");
		return (0);
	}

	stct = 0;
	if (u.ugold)
		stuff[stct++] = '$';
	stuff[stct] = 0;
	for (otmp = invent; otmp; otmp = otmp->nobj) {
		if (!strchr(stuff, otmp->olet)) {
			stuff[stct++] = otmp->olet;
			stuff[stct] = 0;
		}
		if (otmp->unpaid)
			unpd = TRUE;
	}
	if (unpd)
		stuff[stct++] = 'u';
	if (billx)
		stuff[stct++] = 'x';
	stuff[stct] = 0;

	if (stct > 1) {
		pline("What type of object [%s] do you want an inventory of? ",
		      stuff);
		c = readchar();
		if (strchr(quitchars, c))
			return (0);
	} else
		c = stuff[0];

	if (c == '$')
		return (doprgold());

	if (c == 'x' || c == 'X') {
		if (billx)
			doinvbill(1);
		else
			pline("No used-up objects on the shopping bill.");
		return (0);
	}

	if ((c == 'u' || c == 'U') && !unpd) {
		pline("You are not carrying any unpaid objects.");
		return (0);
	}

	stct = 0;
	ilet = 'a';
	for (otmp = invent; otmp; otmp = otmp->nobj) {
		if (flags.invlet_constant)
			ilet = otmp->invlet;
		if (c == otmp->olet || (c == 'u' && otmp->unpaid))
			stuff[stct++] = ilet;
		if (!flags.invlet_constant)
			if (++ilet > 'z')
				ilet = 'A';
	}
	stuff[stct] = '\0';
	if (stct == 0)
		pline("You have no such objects.");
	else
		doinv(stuff);

	return (0);
}

/* look at what is here */
int
dolook(void)
{
	struct obj *otmp, *otmp0 = NULL;
	struct gold *gold = NULL;
	const char *verb = Blind ? "feel" : "see";
	int ct = 0;

	if (!u.uswallow) {
		if (Blind) {
			pline("You try to feel what is lying here on the floor.");
			if (Levitation) {	/* ab@unido */
				pline("You cannot reach the floor!");
				return (1);
			}
		}
		otmp0 = o_at(u.ux, u.uy);
		gold = g_at(u.ux, u.uy);
	}

	if (u.uswallow || (!otmp0 && !gold)) {
		pline("You %s no objects here.", verb);
		return (!!Blind);
	}

	cornline(0, "Things that are here:");
	for (otmp = otmp0; otmp; otmp = otmp->nobj) {
		if (otmp->ox == u.ux && otmp->oy == u.uy) {
			ct++;
			cornline(1, doname(otmp));
			if (Blind && otmp->otyp == DEAD_COCKATRICE && !uarmg) {
				pline("Touching the dead cockatrice is a fatal mistake ...");
				pline("You die ...");
				killer = "dead cockatrice";
				done("died");
			}
		}
	}

	if (gold) {
		char gbuf[30];

		sprintf(gbuf, "%ld gold piece%s",
			gold->amount, plur(gold->amount));
		if (!ct++)
			pline("You %s here %s.", verb, gbuf);
		else
			cornline(1, gbuf);
	}

	if (ct == 1 && !gold) {
		pline("You %s here %s.", verb, doname(otmp0));
		cornline(3, NULL);
	}
	if (ct > 1)
		cornline(2, NULL);
	return (!!Blind);
}

void
stackobj(struct obj *obj)
{
	struct obj *otmp = fobj;

	for (otmp = fobj; otmp; otmp = otmp->nobj)
		if (otmp != obj)
			if (otmp->ox == obj->ox && otmp->oy == obj->oy &&
			    merged(obj, otmp, 1))
				return;
}

/* merge obj with otmp and delete obj if types agree */
static bool
merged(struct obj *otmp, struct obj *obj, bool lose)
{
	if (obj->otyp == otmp->otyp &&
	    obj->unpaid == otmp->unpaid &&
	    obj->spe == otmp->spe &&
	    obj->dknown == otmp->dknown &&
	    obj->cursed == otmp->cursed &&
	    (strchr("%*?!", obj->olet) ||
	     (obj->known == otmp->known &&
	      (obj->olet == WEAPON_SYM && obj->otyp < BOOMERANG)))) {
		otmp->quan += obj->quan;
		otmp->owt += obj->owt;
		if (lose)
			freeobj(obj);
		obfree(obj, otmp);	/* free(obj), bill->otmp */
		return (1);
	} else
		return (0);
}

/*
 * Gold is no longer displayed; in fact, when you have a lot of money,
 * it may take a while before you have counted it all.
 * [Bug: d$ and pickup still tell you how much it was.]
 */
static long goldcounted;

static bool
countgold(void)
{
	if ((goldcounted += 100 * (u.ulevel + 1)) >= u.ugold) {
		long eps = 0;
		if (!rn2(2))
			eps = rnd((int)(u.ugold / 100 + 1));
		pline("You probably have about %ld gold pieces.",
		      u.ugold + eps);
		return (0);	/* done */
	}
	return (1);		/* continue */
}

int
doprgold(void)
{
	if (!u.ugold)
		pline("You do not carry any gold.");
	else if (u.ugold <= 500)
		pline("You are carrying %ld gold pieces.", u.ugold);
	else {
		pline("You sit down in order to count your gold pieces.");
		goldcounted = 500;
		occupation = countgold;
		occtxt = "counting your gold";
	}
	return (1);
}

/* --- end of gold counting section --- */

int
doprwep(void)
{
	if (!uwep)
		pline("You are empty handed.");
	else
		prinv(uwep);
	return (0);
}

int
doprarm(void)
{
	if (!uarm && !uarmg && !uarms && !uarmh)
		pline("You are not wearing any armor.");
	else {
		char lets[6];
		int ct = 0;

		if (uarm)
			lets[ct++] = obj_to_let(uarm);
		if (uarm2)
			lets[ct++] = obj_to_let(uarm2);
		if (uarmh)
			lets[ct++] = obj_to_let(uarmh);
		if (uarms)
			lets[ct++] = obj_to_let(uarms);
		if (uarmg)
			lets[ct++] = obj_to_let(uarmg);
		lets[ct] = 0;
		doinv(lets);
	}
	return (0);
}

int
doprring(void)
{
	if (!uleft && !uright)
		pline("You are not wearing any rings.");
	else {
		char lets[3];
		int ct = 0;

		if (uleft)
			lets[ct++] = obj_to_let(uleft);
		if (uright)
			lets[ct++] = obj_to_let(uright);
		lets[ct] = 0;
		doinv(lets);
	}
	return (0);
}

bool
digit(char c)
{
	return (c >= '0' && c <= '9');
}