#include "bits/stdc++.h" #pragma GCC optimize("Ofast") // Begin Header {{{ using namespace std; #ifndef DEBUG #define dump(...) #endif #define all(x) x.begin(), x.end() #define rep(i, n) for (intmax_t i = 0, i##_limit = (n); i < i##_limit; ++i) #define reps(i, b, e) for (intmax_t i = (b), i##_limit = (e); i <= i##_limit; ++i) #define repr(i, b, e) for (intmax_t i = (b), i##_limit = (e); i >= i##_limit; --i) #define var(Type, ...) Type __VA_ARGS__; input(__VA_ARGS__) constexpr size_t operator""_zu(unsigned long long value) { return value; }; constexpr intmax_t operator""_jd(unsigned long long value) { return value; }; constexpr uintmax_t operator""_ju(unsigned long long value) { return value; }; constexpr int INF = 0x3f3f3f3f; constexpr intmax_t LINF = 0x3f3f3f3f3f3f3f3f_jd; template using MaxHeap = priority_queue, less>; template using MinHeap = priority_queue, greater>; inline void input() {} template inline void input(Head&& head, Tail&&... tail) { cin >> head; input(forward(tail)...); } template inline void input(vector &vec) { for (auto &e: vec) { cin >> e; } } template inline void input(vector> &mat) { for (auto &vec: mat) { input(vec); } } inline void print() { cout << "\n"; } template inline void print(Head&& head, Tail&&... tail) { static constexpr const char *delim[] = {"", " "}; cout << head << delim[sizeof...(tail)]; print(forward(tail)...); } template inline ostream& operator<<(ostream &strm, const vector &vec) { static constexpr const char *delim[] = {" ", ""}; for (const auto &e: vec) { strm << e << delim[&e == &vec.back()]; } return strm; } template inline vector make_v(const T &initValue, size_t sz) { return vector(sz, initValue); } template inline auto make_v(const T &initValue, size_t sz, Args... args) { return vector(initValue, args...))>(sz, make_v(initValue, args...)); } template class FixPoint : Func { public: explicit constexpr FixPoint(Func&& f) noexcept : Func(forward(f)) {} template constexpr decltype(auto) operator()(Args&&... args) const { return Func::operator()(*this, std::forward(args)...); } }; template static inline constexpr decltype(auto) makeFixPoint(Func&& f) noexcept { return FixPoint{forward(f)}; } template inline bool chmax(T &a, const T &b) noexcept { return b > a && (a = b, true); } template inline bool chmin(T &a, const T &b) noexcept { return b < a && (a = b, true); } template inline T diff(const T &a, const T &b) noexcept { return a < b ? b - a : a - b; } // End Header }}} // UnionFind {{{ struct UnionFind { vector tree; explicit UnionFind(const size_t n) : tree(n + 1, -1) {} size_t size(size_t i) { return (-tree[root(i)]); } size_t root(size_t x) { return (tree[x] < 0) ? x : tree[x] = root(tree[x]); } bool same(size_t x, size_t y) { size_t x_root = root(x); size_t y_root = root(y); return (x_root == y_root); } bool unite(size_t x, size_t y) { size_t x_root = root(x); size_t y_root = root(y); if (x_root == y_root) { return false; } else { tree[x_root] += tree[y_root]; tree[y_root] = x_root; return true; } } }; // }}} signed main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); var(size_t, N); UnionFind uf(N); vector> G(N); rep(i, N - 1) { var(size_t, u, v); uf.unite(u, v); G[u].emplace_back(v); G[v].emplace_back(u); } set uni; rep(v, N) { uni.insert(uf.root(v)); } if (uni.size() == 1) { print("Bob"); } else if (uni.size() >= 3) { print("Alice"); } else { const auto f = [&]() -> bool { rep(v, N) { if (G[v].size() != 0 && G[v].size() != 2) { return false; } } return true; }; print(f() ? "Bob" : "Alice"); } return 0; }