static int
minimal_ladders(ladders_rec_t *rec)
{
Vertex *uu, *vv;
int rc = 0;
char *start = rec->start;
char *goal = rec->goal;
/* build the amplified graph gg */
gg = gb_new_graph(0L);
gg->vertices = __g->vertices;
gg->n = __g->n;
(gg->vertices + gg->n)->name = start;
uu = find_word(start, plant_new_edge);
if (!uu) {
uu = gg->vertices + gg->n++;
}
if (strncmp(start, goal, 5) == 0) {
vv = uu;
} else {
(gg->vertices + gg->n)->name = goal;
vv = find_word(goal, plant_new_edge);
if (!vv) {
vv = gg->vertices + gg->n++;
}
}
if (gg->n == __g->n + 2) {
if (hamm_dist(start, goal) == 1) {
gg->n--;
plant_new_edge(uu);
gg->n++;
}
}
/* print the answer */
if (dijkstra(uu, vv, gg, NULL) < 0) {
strbuf_append_printf(&rec->path,
"Sorry, there's no ladder from %s to %s.",
start, goal);
} else {
rc = dijkstra_result(rec, vv);
}
/* remove all traces of gg */
for (uu = __g->vertices + gg->n-1; uu >= __g->vertices+__g->n; uu--) {
register Arc *a;
for (a = uu->arcs; a; a = a->next) {
vv = a->tip;
vv->arcs = vv->arcs->next;
}
uu->arcs = NULL;
}
gb_recycle(gg);
return rc;
}
int main()
{
/*36:*/
#line 716 "./gb_graph.w"
g= gb_new_graph(2L);
if(g==NULL){
fprintf(stderr,"Oops, I couldn't even create a trivial graph!\n");
return-4;
}
u= g->vertices;v= u+1;
u->name= gb_save_string("vertex 0");
v->name= gb_save_string("vertex 1");
/*:36*/
#line 30 "./gb_graph.w"
;
/*18:*/
#line 327 "./gb_graph.w"
if(gb_alloc(0L,s)!=NULL||gb_trouble_code!=2){
fprintf(stderr,"Allocation error 2 wasn't reported properly!\n");return-2;
}
for(;g->vv.I<100;g->vv.I++)if(gb_alloc(100000L,s)){
g->uu.I++;
printf(".");
fflush(stdout);
}
if(g->uu.I<100&&gb_trouble_code!=3){
fprintf(stderr,"Allocation error 1 wasn't reported properly!\n");return-1;
}
if(g->uu.I==0){
fprintf(stderr,"I couldn't allocate any memory!\n");return-3;
}
gb_free(s);
printf("Hey, I allocated %ld00000 bytes successfully. Terrific...\n",g->uu.I);
gb_trouble_code= 0;
/*:18*/
#line 31 "./gb_graph.w"
;
/*38:*/
#line 735 "./gb_graph.w"
if(strncmp(u->name,v->name,7)){
fprintf(stderr,"Something is fouled up in the string storage machinery!\n");
return-5;
}
gb_new_edge(v,u,-1L);
gb_new_edge(u,u,1L);
gb_new_arc(v,u,-1L);
if((edge_trick&(siz_t)(u->arcs))||
(edge_trick&(siz_t)(u->arcs->next->next))||
!(edge_trick&(siz_t)(v->arcs->next)))
printf("Warning: The \"edge trick\" failed!\n");
if(v->name[7]+g->n!=v->arcs->next->tip->name[7]+g->m-2){
fprintf(stderr,"Sorry, the graph data structures aren't working yet.\n");
return-6;
}
/*:38*/
#line 32 "./gb_graph.w"
;
printf("OK, the gb_graph routines seem to work!\n");
return 0;
}
Graph *
geo_hier(long seed,
int nlevels, /* number of levels (=size of following array) */
int edgemeth, /* method of attaching edges */
int aux, /* auxiliary parameter for edge method (threshold) */
geo_parms *pp) /* array of parameter structures, one per level */
{
Graph *newG, *tG, *GG, *srcG, *dstG;
long *numv; /* array of sizes of lower-level graphs */
geo_parms *curparms, workparms[MAXLEVEL];
register i,k,indx;
long dst;
int temp,total,lowsize,otherend,blen,level;
long maxP[MAXLEVEL], maxDiam[MAXLEVEL], wt[MAXLEVEL];
Vertex *np,*vp,*up,*base;
Arc *ap;
char vnamestr[MAXNAMELEN];
if (seed) /* convention: zero seed means don't use */
gb_init_rand(seed);
if (nlevels < 1 || nlevels > MAXLEVEL) {
gb_trouble_code = bad_specs+HIER_TRBL;
return NULL;
}
/* 1 <= nlevels <= MAXLEVEL */
/* copy the parameters so we can modify them, and caller doesn't
* see the changes.
*/
for (level=0; level<nlevels; level++)
bcopy((char *)&pp[level],&workparms[level],sizeof(geo_parms));
level = 0;
gb_trouble_code = 0;
tG = NULL;
do {
gb_recycle(tG);
tG = geo(0L,workparms);
} while (tG != NULL && !isconnected(tG));
if (tG==NULL)
return tG;
maxDiam[0] = fdiam(tG);
maxP[0] = maxDiam[0];
wt[0] = 1;
for (i=1; i<nlevels; i++)
maxDiam[i] = -1;
curparms = workparms;
while (++level < nlevels) {
long tdiam;
curparms++; /* parameters for graphs @ next level */
/* spread out the numbers of nodes per graph at this level */
numv = (long *) calloc(tG->n,sizeof(long));
lowsize = curparms->n;
randomize(numv,tG->n,curparms->n,3*tG->n);
/* create a subordinate graph for each vertex in the "top" graph,
* and add it into the new graph as a whole.
* We construct the subgraphs all at once to ensure that each
* has a unique address.
*/
for (i=0,vp=tG->vertices; i<tG->n; i++,vp++) {
curparms->n = numv[i];
do {
newG = geo(0L,curparms);
if (newG==NULL) return NULL;
} while (!isconnected(newG));
vp->sub = newG;
tdiam = fdiam(newG);
if (tdiam>maxDiam[level])
maxDiam[level] = tdiam;
}
/* do some calculations before "flattening" the top Graph */
total = 0;
for (i=0; i<tG->n; i++) { /* translate node numbers */
temp = numv[i];
numv[i]= total;
total += temp;
}
if (total != tG->n*lowsize) {
fprintf(stderr,"bad size of new graph!\n");
fprintf(stderr,"total %d tG->n %ld lowsize %d\n",total,tG->n,lowsize);
gb_trouble_code = impossible+HIER_TRBL;
return NULL;
}
/* now create what will become the "new" top-level graph */
newG = gb_new_graph(total);
if (newG==NULL) {
gb_trouble_code += HIER_TRBL;
return NULL;
}
/* resolution of the new graph */
newG->Gscale = tG->Gscale * curparms->scale;
/* compute edge weights for this level */
wt[level] = maxP[level-1] + 1;
maxP[level] = (maxDiam[level]*wt[level])
+ (maxDiam[level-1]*maxP[level-1]);
for (i=0,vp=tG->vertices; i<tG->n; i++,vp++) {
strcpy(vnamestr,vp->name); /* base name for all "offspring" */
blen = strlen(vnamestr);
vnamestr[blen] = '.';
GG = tG->vertices[i].sub;
base = newG->vertices + numv[i]; /* start of this node's */
for (k=0,np=base,up=GG->vertices; k<GG->n; k++,np++,up++) {
/* add the node's edges */
for (ap=up->arcs; ap; ap=ap->next) {
otherend = ap->tip - GG->vertices;
if (k < otherend)
gb_new_edge(np,base+otherend,ap->len);
}
/* now set the new node's position */
np->xpos = tG->vertices[i].xpos * curparms->scale + up->xpos;
np->ypos = tG->vertices[i].ypos * curparms->scale + up->ypos;
/* give the "new" node a name by catenating top & bot names */
strcpy(vnamestr+blen+1,up->name);
np->name = gb_save_string(vnamestr);
} /* loop over GG's vertices */
} /* loop over top-level vertices */
/*
* Now we have to transfer the top-level edges to new graph.
* This is done by one of three methods:
* 0: choose a random node in each subgraph
* 1: attach to the smallest-degree non-leaf node in each
* 2: attach to smallest-degree node
* 3: attach to first node with degree less than aux
*/
for (i=0; i<tG->n; i++) {
Vertex *srcp, *dstp;
Graph *srcG, *dstG;
srcG = tG->vertices[i].sub;
if (srcG == NULL) { /* paranoia */
gb_trouble_code = impossible+HIER_TRBL+1;
return NULL;
}
for (ap=tG->vertices[i].arcs; ap; ap=ap->next) {
dst = ap->tip - tG->vertices;
if (i > dst) /* consider each edge only ONCE */
continue;
dstG = ap->tip->sub;
if (dstG == NULL) { /* paranoia */
gb_trouble_code = impossible+HIER_TRBL+1;
return NULL;
}
/* choose endpoints of the top-level edge */
switch (edgemeth) {
case 0: /* choose random node in each */
srcp = srcG->vertices + gb_next_rand()%srcG->n;
dstp = dstG->vertices + gb_next_rand()%dstG->n;
break;
case 1: /* find nonleaf node of least degree in each */
/* This causes problems with graph size < 3 */
if (srcG->n > 2)
srcp = find_small_deg(srcG,NOLEAF);
else
srcp = find_small_deg(srcG,LEAFOK);
if (dstG->n > 2)
dstp = find_small_deg(dstG,NOLEAF);
else
dstp = find_small_deg(dstG,LEAFOK);
break;
case 2: /* find node of smallest degree */
srcp = find_small_deg(srcG,LEAFOK);
dstp = find_small_deg(dstG,LEAFOK);
break;
case 3: /* first node w/degree < aux */
srcp = find_thresh_deg(srcG,aux);
dstp = find_thresh_deg(dstG,aux);
default:
gb_trouble_code = bad_specs+HIER_TRBL;
return NULL;
} /* switch on edgemeth */
/* pointer arithmetic: isn't it fun?
printf("Copying edge from %d to %d\n",
numv[i]+(srcp - srcG->vertices),
numv[dst] + (dstp - dstG->vertices));
*/
if (srcp==NULL || dstp==NULL) {
gb_trouble_code = impossible + HIER_TRBL+2;
return NULL;
}
srcp = newG->vertices + numv[i] + (srcp - srcG->vertices);
dstp = newG->vertices + numv[dst] + (dstp - dstG->vertices);
gb_new_edge(srcp,dstp,idist(srcp,dstp));
} /* for each arc */
} /* for each vertex of top graph */
/* now make the "new" graph the "top" graph and recycle others */
for (i=0,vp=tG->vertices; i<tG->n; i++,vp++)
gb_recycle(vp->sub);
gb_recycle(tG);
tG = newG;
free(numv);
} /* while more levels */
/* Finally, go back and add the policy weights,
* based upon the computed max diameters
* and Max Path lengths.
*/
for (i=0; i<tG->n; i++)
for (ap=tG->vertices[i].arcs; ap; ap=ap->next) {
dst = ap->tip - tG->vertices;
if (i > dst) /* consider each edge only ONCE */
continue;
assert(i != dst); /* no self loops */
/* i < dst: it is safe to refer to ap's mate by ap+1. */
level = edge_level(&tG->vertices[i],&tG->vertices[dst],nlevels);
ap->policywt = (ap+1)->policywt = wt[level];
}
/* construct the utility and id strings for the new graph.
* Space constraints will restrict us to keeping about 4 levels'
* worth of info.
*/
{
char buf[ID_FIELD_SIZE+1];
register char *cp;
int len, nextlen, left;
strcpy(tG->util_types,GEO_UTIL); /* same for all geo graphs, */
/* defined in geo.h */
cp = tG->id;
sprintf(cp,"geo_hier(%ld,%d,%d,%d,[",seed,nlevels,edgemeth,aux);
len = strlen(cp);
left = ID_FIELD_SIZE - len;
cp += len;
for (i=0; (i < nlevels) && (left > 0); i++) {
nextlen = printparms(buf,&pp[i]);
strncpy(cp,buf,left);
left -= nextlen;
cp += nextlen;
}
if (left > 0) {
sprintf(buf,"])");
nextlen = strlen(buf);
strncpy(cp,buf,left);
}
}
return tG;
} /* geo_hier() */
//#line 6 "../PROTOTYPES/ladders.ch"
int main(int argc, char *argv[])
//#line 94 "../ladders.w"
{
/*5:*/
//#line 120 "../ladders.w"
while (--argc) {
if (strcmp(argv[argc], "-v") == 0)
verbose = 1;
else if (strcmp(argv[argc], "-a") == 0)
alph = 1;
else if (strcmp(argv[argc], "-f") == 0)
freq = 1;
else if (strcmp(argv[argc], "-h") == 0)
heur = 1;
else if (strcmp(argv[argc], "-e") == 0)
echo = 1;
else if (sscanf(argv[argc], "-n%lu", &n) == 1)
randm = 0;
else if (sscanf(argv[argc], "-r%lu", &n) == 1)
randm = 1;
else if (sscanf(argv[argc], "-s%ld", &seed) == 1);
else {
fprintf(stderr, "Usage: %s [-v][-a][-f][-h][-e][-nN][-rN][-sN]\n", argv[0]);
return -2;
}
}
if (alph || randm)
freq = 0;
if (freq)
heur = 0;
/*:5*/
//#line 95 "../ladders.w"
;
/*6:*/
//#line 149 "../ladders.w"
g = words(n, (randm ? zero_vector : NULL), 0L, seed);
quit_if(g == NULL, panic_code);
/*8:*/
//#line 165 "../ladders.w"
if (verbose) {
if (alph)
printf("(alphabetic distance selected)\n");
if (freq)
printf("(frequency-based distances selected)\n");
if (heur)
printf("(lowerbound heuristic will be used to focus the search)\n");
if (randm)
printf("(random selection of %ld words with seed %ld)\n", g->n, seed);
else
printf("(the graph has %ld words)\n", g->n);
}
/*:8*/
//#line 152 "../ladders.w"
;
/*9:*/
//#line 183 "../ladders.w"
if (alph) {
register Vertex *u;
for (u = g->vertices + g->n - 1; u >= g->vertices; u--) {
register Arc *a;
register char *p = u->name;
for (a = u->arcs; a; a = a->next) {
register char *q = a->tip->name;
a->len = a_dist(a->loc);
}
}
} else if (freq) {
register Vertex *u;
for (u = g->vertices + g->n - 1; u >= g->vertices; u--) {
register Arc *a;
for (a = u->arcs; a; a = a->next)
a->len = freq_cost(a->tip);
}
}
/*:9*/
//#line 153 "../ladders.w"
;
/*10:*/
//#line 202 "../ladders.w"
if (alph || freq || heur) {
init_queue = init_128;
del_min = del_128;
enqueue = enq_128;
requeue = req_128;
}
/*:10*/
//#line 154 "../ladders.w"
;
/*:6*/
//#line 96 "../ladders.w"
;
while (1) {
/*26:*/
//#line 373 "../ladders.w"
putchar('\n');
restart:
if (prompt_for_five("Starting", start) != 0)
break;
if (prompt_for_five(" Goal", goal) != 0)
goto restart;
/*:26*/
//#line 98 "../ladders.w"
;
/*13:*/
//#line 245 "../ladders.w"
/*14:*/
//#line 251 "../ladders.w"
gg = gb_new_graph(0L);
quit_if(gg == NULL, no_room + 5);
gg->vertices = g->vertices;
gg->n = g->n;
/*15:*/
//#line 266 "../ladders.w"
(gg->vertices + gg->n)->name = start;
uu = find_word(start, plant_new_edge);
if (!uu)
uu = gg->vertices + gg->n++;
/*:15*/
//#line 256 "../ladders.w"
;
/*16:*/
//#line 272 "../ladders.w"
if (strncmp(start, goal, 5) == 0)
vv = uu;
else {
(gg->vertices + gg->n)->name = goal;
vv = find_word(goal, plant_new_edge);
if (!vv)
vv = gg->vertices + gg->n++;
}
/*:16*/
//#line 257 "../ladders.w"
;
if (gg->n == g->n + 2) /*19: */
//#line 311 "../ladders.w"
if (hamm_dist(start, goal) == 1) {
gg->n--;
plant_new_edge(uu);
gg->n++;
}
/*:19*/
//#line 258 "../ladders.w"
;
quit_if(gb_trouble_code, no_room + 6);
/*:14*/
//#line 246 "../ladders.w"
;
/*21:*/
//#line 333 "../ladders.w"
if (!heur)
min_dist = dijkstra(uu, vv, gg, NULL);
else if (alph)
min_dist = dijkstra(uu, vv, gg, alph_heur);
else
min_dist = dijkstra(uu, vv, gg, hamm_heur);
/*:21*/
//#line 247 "../ladders.w"
;
/*24:*/
//#line 350 "../ladders.w"
if (min_dist < 0)
printf("Sorry, there's no ladder from %s to %s.\n", start, goal);
else
print_dijkstra_result(vv);
/*:24*/
//#line 248 "../ladders.w"
;
/*25:*/
//#line 360 "../ladders.w"
for (uu = g->vertices + gg->n - 1; uu >= g->vertices + g->n; uu--) {
register Arc *a;
for (a = uu->arcs; a; a = a->next) {
vv = a->tip;
vv->arcs = vv->arcs->next;
}
uu->arcs = NULL;
}
gb_recycle(gg);
/*:25*/
//#line 249 "../ladders.w"
;
/*:13*/
//#line 100 "../ladders.w"
;
}
return 0;
}
Graph *
geo(long seed, geo_parms *pp)
{
double p,d,L,radius,r;
u_char *occ;
register int scale;
unsigned nbytes, index, x, y;
u_long units,pertrange;
int mallocd;
register i,j;
Graph *G;
Vertex *up,*vp;
char namestr[128];
gb_trouble_code = 0;
if (seed) /* zero seed means "already init'd */
gb_init_rand(seed);
scale = pp->scale;
L = sqrt(2.0) * scale;
gb_trouble_code = 0;
if ((pp->alpha <= 0.0) || (pp->alpha > 1.0)) gb_trouble_code=bad_specs+1;
if (pp->gamma < 0.0) gb_trouble_code=bad_specs+GEO_TRBL;
if (pp->beta < 0.0) gb_trouble_code=bad_specs+GEO_TRBL;
if (pp->n > (scale * scale)) gb_trouble_code=bad_specs+GEO_TRBL;
if (gb_trouble_code)
return NULL;
radius = pp->gamma * L; /* comes in as a fraction of diagonal */
#define posn(x,y) ((x)*scale)+(y)
#define bitset(v,i) (v[(i)/NBBY]&(1<<((i)%NBBY)))
#define setbit(v,i) v[(i)/NBBY] |= (1<<((i)%NBBY))
/* create a new graph structure */
if ((G=gb_new_graph(pp->n)) == NULL)
return NULL;
nbytes = ((scale*scale)%NBBY ? (scale*scale/NBBY)+1 : (scale*scale)/NBBY);
if (nbytes < STACKMAX) { /* small amount - just do it in the stack */
occ = (u_char *) alloca(nbytes);
mallocd = 0;
} else {
occ = (u_char *) malloc(nbytes);
mallocd = 1;
}
for (i=0; i<nbytes; i++) occ[i] = 0;
/* place each of n points in the plane */
for (i=0,vp = G->vertices; i<pp->n; i++,vp++) {
sprintf(namestr,"%d",i); /* name is just node number */
vp->name = gb_save_string(namestr);
do {
vp->xpos = gb_next_rand()%scale; /* position: 0..scale-1 */
vp->ypos = gb_next_rand()%scale; /* position: 0..scale-1 */
index = posn(vp->xpos,vp->ypos);
} while (bitset(occ,index));
setbit(occ,index);
}
/* Now go back and add the edges */
for (i=0,up = G->vertices; i<(pp->n)-1; i++,up++)
for (j=i+1, vp = &G->vertices[i+1]; j<pp->n; j++,vp++) {
d = distance(up,vp);
switch (pp->method) {
case RG2: /* Waxman's */
d = randfrac()*L;
/* fall through */
case RG1: /* Waxman's */
p = pp->alpha * exp(-d/(L*pp->beta));
break;
case RANDOM: /* the classic */
p = pp->alpha;
break;
case EXP:
p = pp->alpha * exp(-d/(L-d));
break;
case DL: /* Doar-Leslie */
p = pp->alpha * (pp->gamma/pp->n) * exp(-d/(L*pp->beta));
break;
case LOC: /* Locality model, two probabilities */
if (d <= radius) p = pp->alpha;
else p = pp->beta;
break;
default:
die("Bad edge method in geo()!");
}
if (randfrac() < p)
gb_new_edge(up,vp,(int)rint(d));
}
/* Fill in the "id" string to say how the graph was created */
G->Gscale = scale;
sprintf(G->id,"geo(%ld,", seed);
i = strlen(G->id);
i += printparms(G->id+i,pp);
G->id[i] = ')';
G->id[i+1] = (char) 0;
strcpy(G->util_types,GEO_UTIL);
/* clean up */
if (mallocd) free(occ);
return G;
}
