static int regularity_degree(graph *g, int n)
{
if (n == 0) {
return 0;
}
int deg0 = POPCOUNT(*GRAPHROW(g, 0, MAXM));
for (int i = 1; i < n; i++) {
set *gv = GRAPHROW(g, i, MAXM);
int deg = POPCOUNT(*gv);
if (deg != deg0) {
return -1; /* not regular */
}
}
return deg0;
}
static boolean
distinvar(graph *g, int *invar, int n1, int n2)
/* make distance invariant/
exit immediately FALSE if n-1 not maximal else exit TRUE
Note: only invar[n1..n1+n2-1] set */
{
int w,n;
setword workset,frontier;
setword sofar;
int inv,d,v;
n = n1 + n2;
for (v = n-1; v >= n1; --v)
{
inv = 0;
sofar = frontier = bit[v];
for (d = 1; frontier != 0; ++d)
{
workset = 0;
inv += POPCOUNT(frontier) ^ (0x57 + d);
while (frontier)
{
w = FIRSTBITNZ(frontier);
frontier &= ~bit[w];
workset |= g[w];
}
frontier = workset & ~sofar;
sofar |= frontier;
}
invar[v] = inv;
if (v < n-1 && inv > invar[n-1]) return FALSE;
}
return TRUE;
}
static boolean
hitinvar(graph *g, int *invar, int n)
/* make hitting invariant
* return FALSE if n-1 not maximal else return TRUE */
{
setword x,y,z;
int inv,i,v,d;
for (v = n-1; v >= 0; --v)
{
inv = 0;
x = y = g[v];
while (y)
{
TAKEBIT(i,y);
z = x & g[i];
d = POPCOUNT(z);
if (d > inv) inv = d;
}
invar[v] = inv;
if (v < n-1 && inv > invar[n-1]) return FALSE;
}
return TRUE;
}
void
degstats(graph *g, int m, int n, unsigned long *edges, int *mindeg,
int *mincount, int *maxdeg, int *maxcount, boolean *eulerian)
/* Compute degree-related graph properties.
*edges = number of edges
*mindeg, *mincount = minimum degree and how many there are
*maxdeg, *maxcount = maximum degree and how many there are
*eulerian = whether the graph has only even degrees
*/
{
setword *pg;
int i,j,d,dor;
int mind,mindc,maxd,maxdc;
unsigned long ned;
mind = n;
mindc = 0;
maxd = 0;
maxdc = 0;
ned = 0;
dor = 0;
pg = (setword*)g;
for (i = 0; i < n; ++i)
{
d = 0;
for (j = 0; j < m; ++j, ++pg)
if (*pg) d += POPCOUNT(*pg);
if (d == mind)
++mindc;
else if (d < mind)
{
mind = d;
mindc = 1;
}
if (d == maxd)
++maxdc;
else if (d > maxd)
{
maxd = d;
maxdc = 1;
}
dor |= d;
ned += d;
}
*mindeg = mind;
*mincount = mindc;
*maxdeg = maxd;
*maxcount = maxdc;
*edges = ned / 2;
*eulerian = (dor & 1) == 0;
}
boolean
issubconnected(graph *g, set *sub, int m, int n)
/* Test if the subset of g induced by sub is connected. Empty is connected. */
{
int i,head,tail,w,subsize;
set *gw;
#if MAXN
int queue[MAXN],visited[MAXN];
setword subw[MAXM];
#else
DYNALLSTAT(int,queue,queue_sz);
DYNALLSTAT(int,visited,visited_sz);
DYNALLSTAT(set,subw,subw_sz);
DYNALLOC1(int,queue,queue_sz,n,"issubconnected");
DYNALLOC1(int,visited,visited_sz,n,"issubconnected");
DYNALLOC1(set,subw,subw_sz,m,"issubconnected");
#endif
subsize = 0;
for (i = 0; i < m; ++i) subsize += (sub[i] ? POPCOUNT(sub[i]) : 0);
if (subsize <= 1) return TRUE;
for (i = 0; i < n; ++i) visited[i] = 0;
i = nextelement(sub,m,-1);
queue[0] = i;
visited[i] = 1;
head = 0;
tail = 1;
while (head < tail)
{
w = queue[head++];
gw = GRAPHROW(g,w,m);
for (i = 0; i < m; ++i) subw[i] = gw[i] & sub[i];
for (i = -1; (i = nextelement(subw,m,i)) >= 0;)
{
if (!visited[i])
{
visited[i] = 1;
queue[tail++] = i;
}
}
}
return tail == subsize;
}
void
commonnbrs(graph *g, int *minadj, int *maxadj, int *minnon, int *maxnon,
int m, int n)
/* Count the common neighbours of pairs of vertices, and give the minimum
and maximum for adjacent and non-adjacent vertices. Undirected only.
Null minimums are n+1 and null maximums are -1.
*/
{
int j,k;
int mina,maxa,minn,maxn;
int cn;
set *gi,*gj;
setword w;
mina = minn = n+1;
maxa = maxn = -1;
for (j = 0, gj = g; j < n; ++j, gj += m)
for (gi = g; gi != gj; gi += m)
{
cn = 0;
for (k = 0; k < m; ++k)
{
w = gi[k] & gj[k];
if (w) cn += POPCOUNT(w);
}
if (ISELEMENT(gi,j))
{
if (cn < mina) mina = cn;
if (cn > maxa) maxa = cn;
}
else
{
if (cn < minn) minn = cn;
if (cn > maxn) maxn = cn;
}
}
*minadj = mina;
*maxadj = maxa;
*minnon = minn;
*maxnon = maxn;
}
boolean
isconnected1(graph *g, int n)
/* test if g is connected (m=1) */
{
setword seen,expanded,toexpand;
int i;
seen = bit[0];
expanded = 0;
while ((toexpand = (seen & ~expanded)) != 0)
{
i = FIRSTBITNZ(toexpand);
expanded |= bit[i];
seen |= g[i];
}
return POPCOUNT(seen) == n;
}
long
pathcount1(graph *g, int start, setword body, setword last)
/* Number of paths in g starting at start, lying within body and
ending in last. {start} and last should be disjoint subsets of body. */
{
long count;
setword gs,w;
int i;
gs = g[start];
w = gs & last;
count = POPCOUNT(w);
body &= ~bit[start];
w = gs & body;
while (w)
{
TAKEBIT(i,w);
count += pathcount1(g,i,body,last&~bit[i]);
}
return count;
}
static boolean
accept2(graph *g, int n2, int x, graph *gx, int *deg, boolean nuniq)
/* decide if n in theta(g+x) -- version for n+1 == maxn */
{
int i,n;
int lab[MAXN],ptn[MAXN],orbits[MAXN];
int degx[MAXN],invar[MAXN];
setword vmax,gv;
int qn,qv;
int count[MAXN];
int xw;
int nx,numcells,code;
int degn,i0,i1,j,j0,j1;
set active[MAXM];
statsblk stats;
static DEFAULTOPTIONS_GRAPH(options);
setword workspace[50];
#ifdef INSTRUMENT
++a2calls;
if (nuniq) ++a2uniq;
#endif
n = n1 + n2;
nx = n + 1;
for (i = 0; i < n; ++i)
{
gx[i] = g[i];
degx[i] = deg[i];
}
gx[n] = 0;
degx[n] = degn = XPOPCOUNT(x);
xw = x;
while (xw)
{
i = XNEXTBIT(xw);
xw &= ~xbit[i];
gx[i] |= bit[n];
gx[n] |= bit[i];
++degx[i];
}
#ifdef PRUNE1
if (PRUNE1(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (nuniq)
{
#ifdef INSTRUMENT
++a2succs;
#endif
#ifdef PRUNE2
if (PRUNE2(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (canonise) makecanon(gx,gcan,n1,n2+1);
return TRUE;
}
for (i = 0; i < n1; ++i)
{
lab[i] = i;
ptn[i] = 1;
}
ptn[n1-1] = 0;
i0 = n1;
i1 = n;
for (i = n1; i < nx; ++i)
{
if (degx[i] == degn) lab[i1--] = i;
else lab[i0++] = i;
ptn[i] = 1;
}
ptn[n] = 0;
if (i0 == n1)
{
numcells = 2;
active[0] = bit[0] | bit[n1];
if (!distinvar(gx,invar,n1,n2+1)) return FALSE;
qn = invar[n];
j0 = n1;
j1 = n;
while (j0 <= j1)
{
j = lab[j0];
qv = invar[j];
if (qv < qn)
++j0;
else
{
lab[j0] = lab[j1];
lab[j1] = j;
--j1;
}
}
if (j0 > n1)
{
if (j0 == n)
{
#ifdef INSTRUMENT
++a2succs;
#endif
#ifdef PRUNE2
if (PRUNE2(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (canonise) makecanon(gx,gcan,n1,n2+1);
return TRUE;
}
ptn[j1] = 0;
++numcells;
active[0] |= bit[j0];
}
}
else
{
numcells = 3;
ptn[i1] = 0;
active[0] = bit[0] | bit[n1] | bit[i1+1];
vmax = 0;
j = MAXN;
for (i = 0; i < n1; ++i)
if (degx[i] < j && degx[i] > 0)
{
j = degx[i];
vmax = bit[i];
}
else if (degx[i] == j)
vmax |= bit[i];
gv = gx[n] & vmax;
qn = POPCOUNT(gv);
j0 = i1+1;
j1 = n;
while (j0 <= j1)
{
j = lab[j0];
gv = gx[j] & vmax;
qv = POPCOUNT(gv);
if (qv > qn)
return FALSE;
else if (qv < qn)
++j0;
else
{
lab[j0] = lab[j1];
lab[j1] = j;
--j1;
}
}
if (j0 > i1+1)
{
if (j0 == n)
{
#ifdef INSTRUMENT
++a2succs;
#endif
#ifdef PRUNE2
if (PRUNE2(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (canonise) makecanon(gx,gcan,n1,n2+1);
return TRUE;
}
ptn[j1] = 0;
++numcells;
active[0] |= bit[j0];
}
}
refinex(gx,lab,ptn,0,&numcells,count,active,TRUE,&code,1,nx);
if (code < 0)
return FALSE;
else if (code > 0 || numcells >= nx-4)
{
#ifdef INSTRUMENT
++a2succs;
#endif
#ifdef PRUNE2
if (PRUNE2(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (canonise) makecanon(gx,gcan,n1,n2+1);
return TRUE;
}
options.writemarkers = FALSE;
options.writeautoms = FALSE;
options.getcanon = TRUE;
options.defaultptn = FALSE;
active[0] = 0;
#ifdef INSTRUMENT
++a2nauty;
#endif
nauty(gx,lab,ptn,active,orbits,&options,&stats,workspace,50,1,nx,gcan);
if (orbits[lab[n]] == orbits[n])
{
#ifdef INSTRUMENT
++a2succs;
#endif
#ifdef PRUNE2
if (PRUNE2(gx,degx,n1,n2+1,maxn2)) return FALSE;
#endif
if (canonise) makecanon(gx,gcan,n1,n2+1);
return TRUE;
}
else
return FALSE;
}
static void
refinex(graph *g, int *lab, int *ptn, int level, int *numcells,
int *count, set *active, boolean goodret,
int *code, int m, int n)
{
int i,c1,c2,labc1;
setword x;
int split1,split2,cell1,cell2;
int cnt,bmin,bmax;
set *gptr;
setword workset;
int workperm[MAXN];
int bucket[MAXN+2];
if (n == 1)
{
*code = 1;
return;
}
*code = 0;
split1 = -1;
while (*numcells < n && ((split1 = nextelement(active,1,split1)) >= 0
|| (split1 = nextelement(active,1,-1)) >= 0))
{
DELELEMENT1(active,split1);
for (split2 = split1; ptn[split2] > 0; ++split2)
{}
if (split1 == split2) /* trivial splitting cell */
{
gptr = GRAPHROW(g,lab[split1],1);
for (cell1 = 0; cell1 < n; cell1 = cell2 + 1)
{
for (cell2 = cell1; ptn[cell2] > 0; ++cell2) {}
if (cell1 == cell2) continue;
c1 = cell1;
c2 = cell2;
while (c1 <= c2)
{
labc1 = lab[c1];
if (ISELEMENT1(gptr,labc1))
++c1;
else
{
lab[c1] = lab[c2];
lab[c2] = labc1;
--c2;
}
}
if (c2 >= cell1 && c1 <= cell2)
{
ptn[c2] = 0;
++*numcells;
ADDELEMENT1(active,c1);
}
}
}
else /* nontrivial splitting cell */
{
workset = 0;
for (i = split1; i <= split2; ++i)
workset |= bit[lab[i]];
for (cell1 = 0; cell1 < n; cell1 = cell2 + 1)
{
for (cell2 = cell1; ptn[cell2] > 0; ++cell2) {}
if (cell1 == cell2) continue;
i = cell1;
if ((x = workset & g[lab[i]])) /* not == */
cnt = POPCOUNT(x);
else
cnt = 0;
count[i] = bmin = bmax = cnt;
bucket[cnt] = 1;
while (++i <= cell2)
{
if ((x = workset & g[lab[i]])) /* not == */
cnt = POPCOUNT(x);
else
cnt = 0;
while (bmin > cnt) bucket[--bmin] = 0;
while (bmax < cnt) bucket[++bmax] = 0;
++bucket[cnt];
count[i] = cnt;
}
if (bmin == bmax) continue;
c1 = cell1;
for (i = bmin; i <= bmax; ++i)
if (bucket[i])
{
c2 = c1 + bucket[i];
bucket[i] = c1;
if (c1 != cell1)
{
ADDELEMENT1(active,c1);
++*numcells;
}
if (c2 <= cell2) ptn[c2-1] = 0;
c1 = c2;
}
for (i = cell1; i <= cell2; ++i)
workperm[bucket[count[i]]++] = lab[i];
for (i = cell1; i <= cell2; ++i)
lab[i] = workperm[i];
}
}
if (ptn[n-2] == 0)
{
if (lab[n-1] == n-1)
{
*code = 1;
if (goodret) return;
}
else
{
*code = -1;
return;
}
}
else
{
i = n - 1;
while (1)
{
if (lab[i] == n-1) break;
--i;
if (ptn[i] == 0)
{
*code = -1;
return;
}
}
}
}
}
int
static main(int argc, char *argv[])
{
int i,j,bad;
setword w,ww;
printf("NAUTYVERSION=%s NAUTYVERSIONID=%d\n",
NAUTYVERSION,NAUTYVERSIONID);
printf("MAXN=%d MAXM=%d WORDSIZE=%d NAUTY_INFINITY=%d\n",
MAXN,MAXM,WORDSIZE,NAUTY_INFINITY);
printf("sizes: short=%d int=%d long=%d double=%d\n",
(int)sizeof(short),(int)sizeof(int),(int)sizeof(long),
(int)sizeof(double));
printf("sizes: boolean=%d setword=%d\n",
(int)sizeof(boolean),(int)sizeof(setword));
printf("CLZ=%d,%d,%d\n",HAVE_CLZ,HAVE_CLZL,HAVE_CLZLL);
#if SIZEOF_LONGLONG > 0
printf("sizeof(long long)=%d\n",sizeof(long long));
#endif
printf("defined:");
#ifdef __STDC__
printf(" __STDC__");
#endif
#ifdef BIGNAUTY
printf(" BIGNAUTY(obsolete!)");
#endif
#ifdef SYS_UNIX
printf(" SYS_UNIX");
#endif
#ifdef SYS_CRAY
printf(" SYS_CRAY");
#endif
#ifdef SETWORD_SHORT
printf(" SETWORD_SHORT");
#endif
#ifdef SETWORD_INT
printf(" SETWORD_INT");
#endif
#ifdef SETWORD_LONG
printf(" SETWORD_LONG");
#endif
#ifdef SETWORD_LONGLONG
printf(" SETWORD_LONGLONG");
#endif
printf("\n");
bad = 0;
if (8*sizeof(setword) != WORDSIZE)
{
printf("\n ***** NOTE: WORDSIZE mismatch *****\n\n");
++bad;
}
for (i = 0; i < WORDSIZE; ++i)
{
w = ALLMASK(i);
if (POPCOUNT(w) != i)
{
printf("\n ***** POPCOUNT(ALLMASK) error %d *****\n\n",i);
++bad;
}
}
for (i = 0; i < WORDSIZE; ++i)
{
w = BITMASK(i);
if (POPCOUNT(w) != WORDSIZE-i-1)
{
printf("\n ***** POPCOUNT(BITMASK) error %d *****\n\n",i);
++bad;
}
}
for (i = 0; i < WORDSIZE; ++i)
if (POPCOUNT(ALLMASK(i)) != i)
{
printf("\n ***** POPCOUNT(ALLMASK) error %d *****\n\n",i);
++bad;
}
for (i = 0; i < WORDSIZE; ++i)
if (FIRSTBIT(BITT[i]) != i)
{
printf("\n ***** FIRSTBIT(BITT) error %d *****\n\n",i);
++bad;
}
if (FIRSTBIT((setword)0) != WORDSIZE)
{
printf("\n ***** FIRSTBIT(0) error *****\n\n");
++bad;
}
for (i = 0; i < WORDSIZE; ++i)
if (POPCOUNT(BITT[i]) != 1)
{
printf("\n ***** POPCOUNT(BITT) error %d *****\n\n",i);
++bad;
}
for (i = 0; i < WORDSIZE; ++i)
{
w = 0;
for (j = 1; j <= WORDSIZE; ++j)
{
w |= BITT[(j*97+i)%WORDSIZE];
if (POPCOUNT(w) != j)
{
printf("\n ***** POPCOUNT(w) error %d %d *****\n\n",i,j);
++bad;
}
}
}
if (!bad) printf("\nNo errors found\n");
else printf("\nXXXXXXX %d errors found XXXXXXX\n",bad);
exit(0);
}
static boolean
accept2(graph *g, int n, xword x, graph *gx, int *deg, boolean nuniq)
/* decide if n in theta(g+x) -- version for n+1 == maxn */
{
int i;
int lab[MAXN],ptn[MAXN],orbits[MAXN];
int degx[MAXN],invar[MAXN];
setword vmax,gv,gxn;
int qn,qv;
int count[MAXN];
int nx,numcells,code;
int degn,i0,i1,j,j0,j1;
set active[MAXM];
statsblk stats;
static DEFAULTOPTIONS_GRAPH(options);
setword workspace[50];
boolean cheapacc;
#ifdef INSTRUMENT
++a2calls;
if (nuniq) ++a2uniq;
#endif
nx = n + 1;
gxn = 0;
for (i = 0; i < n; ++i)
{
if ((xbit[i] & x))
{
gxn |= bit[i];
gx[i] = g[i];
degx[i] = deg[i];
}
else
{
gx[i] = g[i] | bit[n];
degx[i] = deg[i] + 1;
}
}
gx[n] = gxn;
degx[n] = degn = XPOPCOUNT(x);
#ifdef PREPRUNE
if (PREPRUNE(gx,n+1,maxn)) return FALSE;
#endif
if (nuniq)
{
#ifdef INSTRUMENT
++a2succs;
#endif
if (canonise) makecanon(gx,gcan,nx);
return TRUE;
}
i0 = 0;
i1 = n;
for (i = 0; i < nx; ++i)
{
if (degx[i] == degn) lab[i1--] = i;
else lab[i0++] = i;
ptn[i] = 1;
}
ptn[n] = 0;
if (i0 == 0)
{
numcells = 1;
active[0] = bit[0];
if (!hitinvar(gx,invar,nx)) return FALSE;
qn = invar[n];
j0 = 0;
j1 = n;
while (j0 <= j1)
{
j = lab[j0];
qv = invar[j];
if (qv < qn)
++j0;
else
{
lab[j0] = lab[j1];
lab[j1] = j;
--j1;
}
}
if (j0 > 0)
{
if (j0 == n)
{
#ifdef INSTRUMENT
++a2succs;
#endif
if (canonise) makecanon(gx,gcan,nx);
return TRUE;
}
ptn[j1] = 0;
++numcells;
active[0] |= bit[j0];
}
}
else
{
numcells = 2;
ptn[i1] = 0;
active[0] = bit[0] | bit[i1+1];
vmax = 0;
for (i = i1+1; i < nx; ++i) vmax |= bit[lab[i]];
gv = gx[n] & vmax;
qn = POPCOUNT(gv);
j0 = i1+1;
j1 = n;
while (j0 <= j1)
{
j = lab[j0];
gv = gx[j] & vmax;
qv = POPCOUNT(gv);
if (qv > qn)
return FALSE;
else if (qv < qn)
++j0;
else
{
lab[j0] = lab[j1];
lab[j1] = j;
--j1;
}
}
if (j0 > i1+1)
{
if (j0 == n)
{
#ifdef INSTRUMENT
++a2succs;
#endif
if (canonise) makecanon(gx,gcan,nx);
return TRUE;
}
ptn[j1] = 0;
++numcells;
active[0] |= bit[j0];
}
}
refinex(gx,lab,ptn,0,&numcells,count,active,TRUE,&code,1,nx);
if (code < 0) return FALSE;
cheapacc = FALSE;
if (code > 0) cheapacc = TRUE;
if (cheapacc)
{
#ifdef INSTRUMENT
++a2succs;
#endif
if (canonise) makecanon(gx,gcan,nx);
return TRUE;
}
options.getcanon = TRUE;
options.digraph = TRUE;
options.defaultptn = FALSE;
active[0] = 0;
#ifdef INSTRUMENT
++a2nauty;
#endif
nauty(gx,lab,ptn,active,orbits,&options,&stats,workspace,50,1,nx,gcan);
if (orbits[lab[n]] == orbits[n])
{
#ifdef INSTRUMENT
++a2succs;
#endif
if (canonise) makecanon(gx,gcan,nx);
return TRUE;
}
else
return FALSE;
}
int
conncontent(graph *g, int m, int n)
/* number of connected spanning subgraphs with an even number
of edges minus the number with an odd number of edges */
{
graph h[WORDSIZE];
setword gj;
int i,j,v1,v2,x,y;
int minv,mindeg,deg,goodv;
long ne;
if (m > 1) ABORT("conncontent only implemented for m=1");
/* First handle tiny graphs */
if (n <= 3)
{
if (n == 1) return 1;
if (n == 2) return (g[0] ? -1 : 0);
if (!g[0] || !g[1] || !g[2]) return 0; /* disconnected */
if (g[0]^g[1]^g[2]) return 1; /* path */
return 2; /* triangle */
}
/* Now compute
ne = number of edges
mindeg = minimum degree
minv = a vertex of minimum degree
goodv = a vertex with a clique neighbourhood (-1 if none)
*/
mindeg = n;
ne = 0;
goodv = -1;
for (j = 0; j < n; ++j)
{
gj = g[j];
deg = POPCOUNT(gj);
ne += deg;
if (deg < mindeg)
{
mindeg = deg;
minv = j;
if (deg == 1) goodv = j;
}
if (deg >= 3 && deg <= 4 && goodv < 0)
{
while (gj)
{
TAKEBIT(i,gj);
if (gj & ~g[i]) break;
}
if (!gj) goodv = j;
}
}
ne /= 2;
/* Cases of isolated vertex or tree */
if (mindeg == 0) return 0;
#if 0
if (mindeg == 1 && ne == n-1)
{
if (isconnected1(g,n)) return ((n&1) ? 1 : -1);
else return 0;
}
#endif
/* Cases of clique and near-clique */
if (mindeg == n-1)
{
j = -1;
for (i = 2; i < n; ++i) j *= -i;
return j;
}
if (mindeg == n-2 && n < 16)
{
if (!knm_computed)
{
knm_computed = TRUE;
knm[1][0] = 1;
for (i = 2; i < 16; ++i)
{
knm[i][0] = -knm[i-1][0] * (i-1);
for (j = 1; j+j <= i; ++j)
knm[i][j] = knm[i][j-1] + knm[i-1][j-1];
}
}
return knm[n][(n*n-n)/2-ne];
}
/* Case of vertex with clique neighbourhood */
if (goodv >= 0)
{
delete1(g,h,goodv,n);
return -POPCOUNT(g[goodv]) * conncontent(h,m,n-1);
}
/* Case of minimum degree 2 */
if (mindeg == 2)
{
x = FIRSTBIT(g[minv]);
y = FIRSTBIT(g[minv]^bit[x]);
if (x > minv) --x;
if (y > minv) --y;
delete1(g,h,minv,n);
v1 = conncontent(h,m,n-1);
if (h[x] & bit[y]) return -2*v1; /* adjacent neighbours */
h[x] |= bit[y];
h[y] |= bit[x];
v2 = conncontent(h,m,n-1);
return -v1 - v2;
}
/* Case of more than 2/3 dense but not complete */
if (3*ne > n*n-n)
{
j = FIRSTBIT(g[minv] ^ bit[minv] ^ ALLMASK(n)); /* non-neighbour */
g[minv] ^= bit[j];
g[j] ^= bit[minv];
v1 = conncontent(g,m,n);
g[minv] ^= bit[j];
g[j] ^= bit[minv];
contract1(g,h,minv,j,n);
v2 = conncontent(h,m,n-1);
return v1 + v2;
}
/* All remaining cases */
j = FIRSTBIT(g[minv]); /* neighbour */
g[minv] ^= bit[j];
g[j] ^= bit[minv];
v1 = conncontent(g,m,n);
g[minv] ^= bit[j];
g[j] ^= bit[minv];
contract1(g,h,minv,j,n);
v2 = conncontent(h,m,n-1);
return v1 - v2;
}
static void
multi(graph *g, int nfixed, long minedges, long maxedges, long maxmult,
int maxdeg, boolean lswitch, int m, int n)
{
static DEFAULTOPTIONS_GRAPH(options);
statsblk stats;
setword workspace[100];
grouprec *group;
int ne;
int i,j,k,j0,j1,thisdeg,maxd,x0,x1;
set *gi;
int lab[MAXNV],ptn[MAXNV],orbits[MAXNV],deg[MAXNV];
int delta[MAXNV],def[MAXNV];
set active[(MAXNV+WORDSIZE-1)/WORDSIZE];
boolean isreg;
#ifdef PATHCOUNTS
++count0;
#endif
j0 = -1; /* last vertex with degree 0 */
j1 = n; /* first vertex with degree > 0 */
ne = 0;
maxd = 0;
for (i = 0, gi = g; i < n; ++i, gi += m)
{
thisdeg = 0;
for (j = 0; j < m; ++j) thisdeg += POPCOUNT(gi[j]);
deg[i] = thisdeg;
if (thisdeg > maxd) maxd = thisdeg;
if (thisdeg == 0) lab[++j0] = i;
else lab[--j1] = i;
ne += thisdeg;
}
ne /= 2;
if (maxdeg >= 0 && maxd > maxdeg) return;
#ifdef PATHCOUNTS
++count1;
#endif
if (Aswitch || Bswitch)
for (i = 0; i < n; ++i)
for (j = 0; j < n; ++j)
edgeno[i][j] = -1;
if (ne == 0 && minedges <= 0
&& (!lswitch || (lswitch && (maxdeg&1) == 0)))
{
trythisone(NULL,lswitch,deg,maxdeg,0,n);
return;
}
#ifdef PATHCOUNTS
++count2;
#endif
k = 0;
for (i = 0, gi = g; i < n; ++i, gi += m)
{
for (j = i; (j = nextelement(gi,m,j)) >= 0; )
{
v0[k] = i;
v1[k] = j;
edgeno[i][j] = edgeno[j][i] = k;
lastlev[i] = lastlev[j] = k;
++k;
}
}
isreg = !lswitch && (maxdeg >= 0 && 2*minedges == n*(long)maxdeg);
/* Case of regular multigraphs */
if (isreg) /* regular case */
/* Condition: def(v) <= total def of neighbours */
{
for (i = 0; i < n; ++i)
{
def[i] = maxdeg - deg[i];
delta[i] = -def[i];
}
for (i = 0; i < k; ++i)
{
x0 = v0[i]; x1 = v1[i];
delta[x0] += def[x1];
delta[x1] += def[x0];
}
for (i = 0; i < n; ++i) if (delta[i] < 0) return;
}
if ((isreg || lswitch) && (maxdeg & n & 1) == 1) return;
if (isreg && j0 >= 0 && maxdeg > 0) return;
if (lswitch && j0 >= 0 && (maxdeg&1) == 1) return;
#ifdef PATHCOUNTS
++count3;
#endif
if (maxedges == NOLIMIT)
{
if (maxmult == NOLIMIT) maxedges = maxdeg*n/2;
else maxedges = ne*maxmult;
}
if (maxmult == NOLIMIT) maxmult = maxedges - ne + 1;
if (maxdeg >= 0 && maxmult > maxdeg) maxmult = maxdeg;
if (maxedges < ne || ne*maxmult < minedges) return;
#ifdef PATHCOUNTS
++count4;
#endif
if (n > MAXNV || ne > MAXNE)
{
fprintf(stderr,">E multig: MAXNV or MAXNE exceeded\n");
exit(1);
}
nauty_check(WORDSIZE,m,n,NAUTYVERSIONID);
for (i = 0; i < n; ++i) ptn[i] = 1;
ptn[n-1] = 0;
EMPTYSET(active,m);
if (j0 != n-1) ADDELEMENT(active,j0+1);
for (i = 0; i <= j0; ++i) ptn[i] = 0;
for (i = j0+1; i < n; ++i)
if (lab[i] < nfixed) break;
if (i != j0+1 && i != n)
{
ptn[i-1] = 0;
ADDELEMENT(active,i);
}
options.defaultptn = FALSE;
options.userautomproc = groupautomproc;
options.userlevelproc = grouplevelproc;
nauty(g,lab,ptn,active,orbits,&options,&stats,workspace,100,m,n,NULL);
if (stats.grpsize2 == 0)
groupsize = stats.grpsize1 + 0.1;
else
groupsize = 0;
group = groupptr(FALSE);
makecosetreps(group);
lastrejok = FALSE;
if (isreg)
scan_reg(0,ne,minedges,maxedges,0,maxmult,group,n,delta,def,maxdeg);
else if (lswitch)
scan_lp(0,ne,minedges,maxedges,0,maxmult,group,n,deg,maxdeg);
else if (maxdeg >= 0)
scan_md(0,ne,minedges,maxedges,0,maxmult,group,n,deg,maxdeg);
else
scan(0,ne,minedges,maxedges,0,maxmult,group,n);
}