（未完成）【CodeChef】KNGHTMOV（DP，SPFA）

  1 const mo=1000000007;
  2 var dp:array[-1000..1000]of int64;
  3     x,y,a,b:array[-2000..2000]of longint;
  4     fac,exf:array[0..2000]of int64;
  5     q,time:array[-2000..2000]of longint;
  6     inq:array[-1000..1000]of boolean;
  7     cas,v,n1,m1,k,i,ax,bx,ay,by:longint;
  8
  9 procedure swap(var x,y:longint);
 10 var t:longint;
 11 begin
 12  t:=x; x:=y; y:=t;
 13 end;
 14
 15 procedure qsort(l,r:longint);
 16 var i,j,mid1,mid2:longint;
 17 begin
 18  i:=l; j:=r; mid1:=a[(l+r)>>1]; mid2:=b[(l+r)>>1];
 19  repeat
 20   while (mid1>a[i])or(mid1=a[i])and(mid2>b[i]) do inc(i);
 21   while (mid1<a[j])or(mid1=a[j])and(mid2<b[j]) do dec(j);
 22   if i<=j then
 23   begin
 24    swap(a[i],a[j]);
 25    swap(b[i],b[j]);
 26    inc(i); dec(j);
 27   end;
 28  until i>j;
 29  if l<j then qsort(l,j);
 30  if i<r then qsort(i,r);
 31 end;
 32
 33 function c(x,y:longint):int64;
 34 begin
 35  exit(fac[x]*exf[y] mod mo*exf[x-y] mod mo);
 36 end;
 37
 38 procedure do1;
 39 var i,j,n,tx,ty,st,ed,m:longint;
 40 begin
 41  n:=0;
 42  fillchar(dp,sizeof(dp),0);
 43  fillchar(a,sizeof(a),0);
 44  fillchar(b,sizeof(b),0);
 45  for i:=1 to k do
 46  begin
 47   read(tx,ty);
 48  // if (abs(tx)<=abs(n1))and(abs(ty)<=abs(m1)) then
 49  // begin
 50    inc(n); x[n]:=tx; y[n]:=ty;
 51  // end;
 52  end;
 53  inc(n); x[n]:=0; y[n]:=0;
 54  inc(n); x[n]:=n1; y[n]:=m1;
 55  if n1<0 then
 56  begin
 57   n1:=-n1; m1:=-m1;
 58   for i:=1 to n do
 59   begin
 60    x[i]:=-x[i]; y[i]:=-y[i];
 61   end;
 62  end;
 63  m:=0;
 64  for i:=1 to n do
 65  begin
 66   tx:=(x[i]*by-y[i]*bx) div (ax*by-ay*bx);
 67   if (tx<0)or(tx*(ax*by-ay*bx)<>x[i]*by-y[i]*bx) then continue;
 68   ty:=(x[i]*ay-y[i]*ax) div (ay*bx-ax*by);
 69   if (ty<0)or(ty*(ay*bx-ax*by)<>x[i]*ay-y[i]*ax) then continue;
 70   inc(m); a[m]:=tx; b[m]:=ty;
 71   if (x[i]=n1)and(y[i]=m1) then ed:=m;
 72  end;
 73  qsort(1,m); st:=0;
 74  for i:=1 to ed do
 75  begin
 76   if (a[i]=0)and(b[i]=0) then
 77   begin
 78    dp[i]:=1; st:=i; continue;
 79   end;
 80   if st=0 then continue;
 81   dp[i]:=c(a[i]+b[i],a[i]);
 82   for j:=st+1 to i-1 do
 83    if (a[j]<=a[i])and(b[j]<=b[i]) then
 84     dp[i]:=(dp[i]-dp[j]*c(a[i]+b[i]-a[j]-b[j],a[i]-a[j]) mod mo) mod mo;
 85   dp[i]:=(dp[i]+mo) mod mo;
 86  end;
 87  writeln(dp[ed]);
 88
 89 end;
 90
 91 function gcd(x,y:longint):longint;
 92 var r:longint;
 93 begin
 94  repeat
 95   r:=x mod y;
 96   x:=y;
 97   y:=r;
 98  until r=0;
 99  exit(x);
100 end;
101
102 function spfa:longint;
103 var t,w,t1,w1,u,e,v:longint;
104     p1,p2:boolean;
105 begin
106  fillchar(dp,sizeof(dp),0);
107  fillchar(inq,sizeof(inq),0);
108  fillchar(time,sizeof(time),0);
109  t:=0; t1:=0; w:=1; w1:=1; q[1]:=0; dp[0]:=1; time[0]:=1; p1:=false; p2:=false;
110  while t<w do
111  begin
112   inc(t); inc(t1);
113   if t1=2000 then t1:=1;
114   u:=q[t1]; inq[u]:=false;
115   if (u<-500)or(u>500) then continue;
116   v:=u+ax;
117   if (not inq[v])and(b[v]=0) then
118   begin
119    inc(w); inc(w1);
120    if w1=2000 then w1:=1;
121    q[w1]:=v;
122    dp[v]:=(dp[v]+dp[u]) mod mo;
123    inq[v]:=true; inc(time[v]);
124    if time[0]>1100 then t:=w+1000;
125    if v<-500 then p1:=true;
126    if v>500 then p2:=true;
127   end;
128   v:=u+bx;
129   if (not inq[v])and(b[v]=0) then
130   begin
131    inc(w); inc(w1);
132    if w1=2000 then w1:=1;
133    q[w1]:=v;
134    dp[v]:=(dp[v]+dp[u]) mod mo;
135    inq[v]:=true; inc(time[v]);
136    if time[0]>1100 then t:=w+1000;
137    if v<-500 then p1:=true;
138    if v>500 then p2:=true;
139   end;
140   if p1 and p2 then exit(-1);
141  end;
142  if time[0]>1100 then exit(-1);
143  exit(dp[n1]);
144 end;
145
146 procedure do2;
147 var i,k1,k2,n,tx,ty:longint;
148 begin
149  if ax>bx then
150  begin
151   swap(ax,bx);
152   swap(ay,by);
153  end;
154
155  k1:=gcd(ax,bx); k2:=gcd(ay,by);
156  if (n1 mod k1<>0)or(m1 mod k2<>0) then
157  begin
158   writeln(0);
159   exit;
160  end;
161  fillchar(x,sizeof(x),0);
162  fillchar(y,sizeof(y),0);
163  fillchar(b,sizeof(b),0);
164  n:=0;
165  for i:=1 to k do
166  begin
167   read(tx,ty);
168   if (tx mod k1<>0)or(ty mod k2<>0) then continue;
169   b[tx div k1]:=1;
170  end;
171  n1:=n1 div k1; m1:=m1 div k2;
172  ax:=ax div k1; bx:=bx div k1;
173  writeln(spfa);
174 end;
175
176 begin
177  assign(input,‘1.in‘); reset(input);
178  assign(output,‘1.out‘); rewrite(output);
179  read(cas);
180  fac[0]:=1; exf[0]:=1; exf[1]:=1;
181  for i:=1 to 2000 do fac[i]:=fac[i-1]*i mod mo;
182  for i:=2 to 2000 do exf[i]:=exf[mo mod i]*(mo-mo div i) mod mo;
183  for i:=1 to 2000 do exf[i]:=exf[i-1]*exf[i] mod mo;
184  for v:=1 to cas do
185  begin
186   read(n1,m1,k);
187   read(ax,ay,bx,by);
188   if (ax=0)and(ay=0)and(bx=0)and(by=0) then
189   begin
190    if (n1=0)and(m1=0) then writeln(-1)
191     else writeln(0);
192    continue;
193   end;
194   if (ax=0)and(bx=0)and(n1<>0) then
195   begin
196    writeln(0);
197    continue;
198   end;
199   if (ay=0)and(by=0)and(m1<>0) then
200   begin
201    writeln(0);
202    continue;
203   end;
204   if (ax=0)and(ay<>0)and(bx<>0)and(by=0) then do1
205   else if ax*by=ay*bx then do2
206    else do1;
207  end;
208  close(input);
209  close(output);
210 end.