MOD = 10 ** 9 + 7 class UnionFind: def __init__(self, n): self.n = n self.parents = [-1] * n self.group = n def find(self, x): if self.parents[x] < 0: return x else: self.parents[x] = self.find(self.parents[x]) return self.parents[x] def union(self, x, y): x = self.find(x) y = self.find(y) if x == y: return self.group -= 1 if self.parents[x] > self.parents[y]: x, y = y, x self.parents[x] += self.parents[y] self.parents[y] = x def size(self, x): return -self.parents[self.find(x)] def same(self, x, y): return self.find(x) == self.find(y) def members(self, x): root = self.find(x) return [i for i in range(self.n) if self.find(i) == root] def roots(self): return [i for i, x in enumerate(self.parents) if x < 0] def group_count(self): return self.group def all_group_members(self): dic = {r:[] for r in self.roots()} for i in range(self.n): dic[self.find(i)].append(i) return dic def __str__(self): return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) n = int(input()) abc = [list(map(int, input().split())) for _ in range(n - 1)] ans = 0 bi = 1 for i in range(30): UF = UnionFind(n) for a, b, c in abc: if c >> i & 1: UF.union(a - 1, b - 1) for r in UF.roots(): r = UF.size(r) ans += r * (r - 1) // 2 * bi ans %= MOD bi *= 2 print(ans)