import sys readline = sys.stdin.readline class UnionFind(object): def __init__(self, n=1): self.par = [i for i in range(n)] self.rank = [0 for _ in range(n)] self.size = [1 for _ in range(n)] def find(self, x): if self.par[x] == x: return x else: self.par[x] = self.find(self.par[x]) return self.par[x] def union(self, x, y): x = self.find(x) y = self.find(y) if x != y: if self.rank[x] < self.rank[y]: x, y = y, x if self.rank[x] == self.rank[y]: self.rank[x] += 1 self.par[y] = x self.size[x] += self.size[y] def is_same(self, x, y): return self.find(x) == self.find(y) def get_size(self, x): x = self.find(x) return self.size[x] N = int(readline()) U = UnionFind(N) for i in range(N - 1): w, v = map(int, readline().split()) if U.is_same(w, v): print("Alice") exit() U.union(w, v) print("Bob")