#!/usr/bin/python3
a=int(input())
islands=[[] for x in range(a)]
for i in range(a-1):
    m,n=map(int,input().split(" "))
    islands[m].append(True)
    islands[n].append(True)
for i in range(a-1):
    if len(islands[i]) ==2:
        print("Alice")
        exit()
print("Bob")