Universal Cup Judging System

Universal Cup

Limite de temps : 4.0 s Limite de mémoire : 1024 MB Points totaux : 100 Difficulté: [afficher] Hackable ✓
Statistiques

小青魚有一棵有 $n$ 個頂點嘅樹 $G = (V, E)$。樹嘅頂點用由 $1$ 到 $n$ 嘅正整數編號。第 $i$($1 \le i \le n - 1$)條邊連接住頂點 $u_i$ 同 $v_i$。

小青魚想你為每個頂點 $i$ 分配一個由 $1$ 到 $n$ 嘅正整數 $p_i$,並滿足以下要求:

  • 對於每對 $1 \le i < j \le n$,都有 $p_i \neq p_j$。換句話講,$p_{1 \dots n}$ 構成一個長度為 $n$ 嘅排列。
  • 對於樹上面嘅每條邊 $(u, v) \in E$,都有 $p_u + p_v \le n + 1$。

小青魚想你計出有幾多個排列 $p$ 滿足呢個條件。同平時一樣,因為呢道題係非偶像之作,小青魚唔想你輸出對大質數取模嘅答案。因此,請輸出對 $4$ 取模之後嘅答案。

Input

輸入包含多組測試資料。輸入嘅第一行包含一個整數 $T$($1 \le T$),代表測試資料嘅組數。

對於每組測試資料,第一行包含一個整數 $n$($1 \le n \le 10^6$),代表樹入面嘅頂點數量。

接住落嚟嘅 $(n - 1)$ 行,每行包含兩個整數 $u_i$ 同 $v_i$($1 \le u_i, v_i \le n, u_i \neq v_i$),代表一條連接頂點 $u_i$ 同 $v_i$ 嘅邊。保證呢 $(n - 1)$ 條邊構成一棵合法嘅樹。

保證所有測試資料嘅 $n$ 總和唔超過 $10^6$。

Output

對於每組測試資料,輸出一行包含一個整數,代表對 $4$ 取模之後嘅答案。

Examples

Input 1

4
1
2
1 2
4
3 1
2 1
2 4
4
4 3
3 1
2 3

Output 1

1
2
0
2

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