output_description: Print the number of ways to paint the edges that satisfy all of the M
  conditions.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      a_1 b_1
      :
      a_{N-1} b_{N-1}
      M
      u_1 v_1
      :
      u_M v_M
attempt: # 入力
  N = int(input())
  ab = []
  # 頂点1,3,4が直接つながっている時G[1]=[3,4],G[3]=[1,4],G[4]=[1,3]となるグラフ表現
  G = [[] for i in range(N + 1)]
  for i in range(N - 1):
      ab.append(list(map(int, input().split())))
      G[ab[i][0]].append(ab[i][1])
      G[ab[i][1]].append(ab[i][0])
  
  M = int(input())
  print(M)
  ans = 2 ** (N - 1)
  
  
  for k in range(M):
      u, v = map(int, input().split())
      start = u
      goal = v
      # ノードが探索済みか否かを判別するリスト
      # used[6]=1ならばノード６は探索済み
      used = [0 for y in range(N + 1)]
      d = [100 for y in range(N + 1)]
  
      queue = []
      queue.append(start)
      d[start] = 0
      print(queue)
  
      while len(queue) > 0:
          # キューからノードを取り出して、探索済みにする
          num = queue.pop(0)
          used[num] = 1
  
          # 現在のノードから伸びている枝の数だけ探索
          for j in range(1, len(G[num]) + 1):
              # 探索するノードが未探索かの判定
              if used[G[num][j]] == 0:
                  d[G[num][j]] = d[num] + 1
                  queue.append(G[num][j])
              if G[num][j] == goal:
                  break
          break
  
      ans -= 2 ** d[goal - 1]
  
  print(ans)
  
problem_description: Statement
  
  We have a tree with N vertices numbered 1 to N. The i-th edge in this tree
  connects Vertex a_i and Vertex b_i.  
  Consider painting each of these edges white or black. There are 2^{N-1} such
  ways to paint the edges. Among them, how many satisfy all of the following M
  restrictions?
  
    * The i-th (1 \leq i \leq M) restriction is represented by two integers u_i and v_i, which mean that the path connecting Vertex u_i and Vertex v_i must contain at least one edge painted black.
samples: [{"input": "3\n    1 2\n    2 3\n    1\n    1 3", "output": "3\n    \n\nThe tree in this input is shown below:  \n  \n![Figure](https://img.atcoder.jp/ghi/5b0208ab1e3bb39a5d4fb7bafbfc448e.png)  \n  \nAll of the M restrictions will be satisfied if Edge 1 and 2 are respectively\npainted (white, black), (black, white), or (black, black), so the answer is 3.\n\n* * *"}, {"input": "2\n    1 2\n    1\n    1 2", "output": "1\n    \n\nThe tree in this input is shown below:  \n  \n![Figure](https://img.atcoder.jp/ghi/d08b3f53dfa4857fe9ffe13fa5d7ae69.png)  \n  \nAll of the M restrictions will be satisfied only if Edge 1 is painted black,\nso the answer is 1.\n\n* * *"}, {"input": "5\n    1 2\n    3 2\n    3 4\n    5 3\n    3\n    1 3\n    2 4\n    2 5", "output": "9\n    \n\nThe tree in this input is shown below:  \n  \n![Figure](https://img.atcoder.jp/ghi/386502bb3c85e0bb5aee64e4e7c087a1.png)  \n  \n\n* * *"}, {"input": "8\n    1 2\n    2 3\n    4 3\n    2 5\n    6 3\n    6 7\n    8 6\n    5\n    2 7\n    3 5\n    1 6\n    2 8\n    7 8", "output": "62\n    \n\nThe tree in this input is shown below:  \n  \n![Figure](https://img.atcoder.jp/ghi/955fa8fd8af658abb24ff2f68b9997be.png)"}]