【ZJOI2017 Round1练习】D8T3 stone（Nim游戏）

题意：

思路：与其类似的题是HDU5996

HDU5996为判定性问题，稍加改动就可以用来统计方案数

var a:array[1..1000000]of longint;
    v,cas,i,j,ans,tmp,n,s,k:longint;
begin
 assign(input,'stone.in'); reset(input);
 assign(output,'stone.out'); rewrite(output);
 readln(cas);
 for v:=1 to cas do
 begin
  readln(n); s:=0; k:=0;
  for i:=1 to n do
   for j:=1 to 1<<(i-1) do
   begin
    inc(k); read(a[k]);
    if (n-i) mod 2=0 then s:=s xor a[k];
   end;
  //writeln(s);
  ans:=0; k:=0;
  for i:=1 to n do
   for j:=1 to 1<<(i-1) do
   begin
    inc(k);
    if (n-i) mod 2=0 then
    begin
     tmp:=0 xor (s xor a[k]);
     if tmp<a[k] then
     begin
      if i=n then inc(ans)
       else ans:=ans+2;
     end;
     if (i>1)and(tmp>a[k])and((k>>1)>0)and
       (a[k>>1]>=tmp-a[k]) then inc(ans);
    end;
   end;
  writeln(ans);

 end;

 close(input);
 close(output);
end.