class LinkCutTree(object): def __init__(self, A, dot, e, compose, id, act): n = len(A) self._value = A[:] self._left = [-1] * n self._right = [-1] * n self._parent = [-1] * n self._size = [1] * n self._sum = A[:] self._reverse = [False] * n self._lazy = [id] * n self._dot, self._e, self._compose, self._id, self._act = dot, e, compose, id, act def _state(self, v): if self._parent[v] == -1: return 0 elif self._left[self._parent[v]] == v: return -1 elif self._right[self._parent[v]] == v: return 1 else: return 0 def _push(self, v): left, right = self._left, self._right if self._lazy[v] != self._id: lazy, compose, act = self._lazy, self._compose, self._act self._value[v] = act(lazy[v], self._value[v], 1) self._sum[v] = act(lazy[v], self._sum[v], self._size[v]) if left[v] != -1: lazy[left[v]] = compose(lazy[left[v]], lazy[v]) if right[v] != -1: lazy[right[v]] = compose(lazy[right[v]], lazy[v]) lazy[v] = self._id if self._reverse[v]: reverse = self._reverse left[v], right[v] = right[v], left[v] if left[v] != -1: reverse[left[v]] ^= True if right[v] != -1: reverse[right[v]] ^= True reverse[v] = False def _update(self, v): left, right, size, sum = self._left, self._right, self._size, self._sum size[v] = 1 sum[v] = self._value[v] if left[v] != -1: self._push(left[v]) size[v] += size[left[v]] sum[v] = self._dot(sum[left[v]], sum[v]) if right[v] != -1: self._push(right[v]) size[v] += size[right[v]] sum[v] = self._dot(sum[v], sum[right[v]]) def _rotate(self, v, p, d): left, right, parent = self._left, self._right, self._parent reverse, lazy = self._reverse, self._lazy self._push(v) if d == -1: left[p] = right[v] if right[v] != -1: parent[right[v]] = p right[v], parent[p] = p, v elif d == 1: right[p] = left[v] if left[v] != -1: parent[left[v]] = p left[v], parent[p] = p, v reverse[v], reverse[p] = reverse[p], False lazy[v], lazy[p] = lazy[p], self._id self._update(p) def _splay(self, v): left, right, parent = self._left, self._right, self._parent state, rotate = self._state, self._rotate p, dp = parent[v], state(v) while dp: g, dg = parent[p], state(p) if dg: np, ndp = parent[g], state(g) if dp == dg: rotate(p, g, dg) rotate(v, p, dp) else: rotate(v, p, dp) rotate(v, g, dg) p, dp = np, ndp else: rotate(v, p, dp) parent[v] = g break else: parent[v] = p def _expose(self, v): right, parent = self._right, self._parent update, splay, push = self._update, self._splay, self._push prev, cur = -1, v while cur != -1: splay(cur) push(cur) right[cur] = prev prev, cur = cur, parent[cur] splay(v) update(v) return prev def evert(self, v): self._expose(v) self._reverse[v] ^= True def lca(self, u, v): self._expose(u) return self._expose(v) def link(self, u, v): self.evert(u) self._parent[u] = v def cut(self, v): self._expose(v) self._parent[self._left[v]] = -1 self._left[v] = -1 self._update(v) def is_connected(self, u, v): if u == v: return True self._expose(u) self._expose(v) return self._parent[u] != -1 def act(self, u, v, f): self.evert(u) self._expose(v) self._lazy[v] = self._compose(self._lazy[v], f) def sum(self, u, v): self.evert(u) self._expose(v) return self._sum[v] import sys input = sys.stdin.buffer.readline from operator import add N = int(input()) dot = add e = 0 compose = add id = 0 act = lambda f, val, size: val + f * size tree = LinkCutTree([1] * N, dot, e, compose, id, act) for _ in range(N - 1): u, v = map(int, input().split()) u -= 1 v -= 1 tree.link(u, v) ans = 0 Q = int(input()) for _ in range(Q): u, v = map(int, input().split()) u -= 1 v -= 1 ans += tree.sum(u, v) tree.act(u, v, 1) print(ans)