bzoj2938

显然AC自动机，但什么叫无限生成呢？
显然就是在AC自动机上匹配，出现了一个环（不能走结尾节点）
直接搜索即可

var trie:array[0..30010,'0'..'1'] of longint;
    q,f:array[0..30010] of longint;
    can,v,r:array[0..30010] of boolean;
    l,n,i,t,j,k:longint;
    s:ansistring;

procedure ac;
  var j,x,y,h,r:longint;
      c:char;
  begin
    h:=1;
    r:=0;
    for c:='0' to '1' do
      if trie[0,c]<>0 then
      begin
        inc(r);
        q[r]:=trie[0,c];
      end;
    while h<=r do
    begin
      x:=q[h];
      for c:='0' to '1' do
        if trie[x,c]<>0 then
        begin
          y:=trie[x,c];
          inc(r);
          q[r]:=y;
          j:=f[x];
          while (j>0) and (trie[j,c]=0) do j:=f[j];
          f[y]:=trie[j,c];
          if can[trie[j,c]] then can[y]:=true;
        end;
      inc(h);
    end;
  end;

function dfs(x:longint):boolean;
  var c:char;
      j:longint;
  begin
    if can[x] then exit(false);
    if v[x] then exit(true)
    else v[x]:=true;
    for c:='0' to '1' do
    begin
      j:=x;
      while (j>0) and (trie[j,c]=0) do j:=f[j];
      if r[trie[j,c]] then continue;
      if dfs(trie[j,c]) then exit(true);
    end;
    v[x]:=false;
    r[x]:=true;
    exit(false);
  end;

begin
  readln(n);
  t:=0;
  for i:=1 to n do
  begin
    readln(s);
    l:=length(s);
    j:=0;
    for k:=1 to l do
    begin
      if trie[j,s[k]]=0 then
      begin
        inc(t);
        trie[j,s[k]]:=t;
      end;
      j:=trie[j,s[k]];
    end;
    can[j]:=true;
  end;
  ac;
  if dfs(0) then writeln('TAK') else writeln('NIE');
end.