#include using namespace std; typedef pair pii; typedef long long ll; template using V = vector; template using VV = V>; #define pb push_back #define eb emplace_back #define mp make_pair #define fi first #define se second #define rep(i,n) rep2(i,0,n) #define rep2(i,m,n) for(int i=m;i<(n);i++) #define ALL(c) (c).begin(),(c).end() #ifdef LOCAL #define dump(x) cerr << __LINE__ << " " << #x << " = " << (x) << endl #else #define dump(x) true #endif constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n-1); } template void chmin(T& t, const U& u) { if (t > u) t = u; } template void chmax(T& t, const U& u) { if (t < u) t = u; } template ostream& operator<<(ostream& os, const pair& p) { os<<"("< ostream& operator<<(ostream& os, const vector& v) { os<<"{"; rep(i, v.size()) { if (i) os<<","; os< par, rank; public: void init(int n) { par.resize(n); rank.resize(n); for (int i = 0; i < n; i++) { par[i] = i; rank[i] = 0; } } int find(int x) { if (par[x] == x) return x; else return par[x] = find(par[x]); } void unite(int x, int y) { x = find(x); y = find(y); if (x == y) return ; if (rank[x] < rank[y]) par[x] = y; else { par[y] = x; if (rank[x] == rank[y]) ++rank[x]; } } bool same(int x, int y) { return (find(x) == find(y)); } }; int main() { int N; cin >> N; unionfind uf; uf.init(N); rep(i, N-1) { int a, b; cin >> a >> b; --a; --b; uf.unite(a, b); } map T; rep(i, N) T[uf.find(i)]++; if (T.size() > 2) { puts("Alice"); } else if (T.size() == 1) { puts("Bob"); } else { bool one = 0; for (auto t : T) { if (t.se == 1) { one = 1; } } puts(!one ? "Alice" : "Bob"); } return 0; }