import sys # sys.setrecursionlimit(10**6) int1 = lambda x: int(x)-1 p2D = lambda x: print(*x, sep="\n") def II(): return int(sys.stdin.buffer.readline()) def LI(): return list(map(int, sys.stdin.buffer.readline().split())) def LI1(): return list(map(int1, sys.stdin.buffer.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def BI(): return sys.stdin.buffer.readline().rstrip() def SI(): return sys.stdin.buffer.readline().rstrip().decode() # dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] # dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] dij = [(0, 1), (1, 0), (1, 1), (1, -1)] inf = 10**16 md = 998244353 # md = 10**9+7 class SparseTableMin: def __init__(self, aa): w = len(aa) h = (w-1).bit_length() table = [aa]+[[-1]*w for _ in range(h-1)] tablei1 = table[0] for i in range(1, h): tablei = table[i] for j in range(w-(1 << i)+1): rj = j+(1 << i-1) tablei[j] = min(tablei1[j], tablei1[rj]) tablei1 = tablei self.table = table def min(self, l, r): i = (r-l).bit_length()-1 tablei = self.table[i] Lmin = tablei[l] Rmin = tablei[r-(1 << i)] if Lmin < Rmin: Rmin = Lmin return Rmin class LCA: def __init__(self, et, depth, first): n = len(depth) self.sp = SparseTableMin([(depth[u], u) for u in et]) self.first = first def get_lca(self, u, v): l, r = self.first[u], self.first[v] if l > r: l, r = r, l return self.sp.min(l, r+1)[1] def DFS(to, root=0): stack = [root << 1 | 1] while stack: u, f = divmod(stack.pop(), 2) euler.append(u) if f: first[u] = len(euler)-1 for v, c in to[u]: if v == parent[u]: continue parent[v] = u depth[v] = depth[u]+1 cost[v] = cost[u]+c stack.append(u << 1) stack.append(v << 1 | 1) n = II() to = [[] for _ in range(n)] for _ in range(n-1): u, v, c = LI1() to[u].append((v, c+1)) to[v].append((u, c+1)) cost = [0]*n euler = [] depth = [0]*n first = [0]*n parent = [-1]*n DFS(to) lca = LCA(euler, depth, first) # print(euler) for _ in range(II()): u, v = LI1() w = lca.get_lca(u, v) # print(u,v,w) print(cost[u]+cost[v]-cost[w]*2)