#include // {{{ #include #ifdef __cpp_lib_ranges_enumerate #include namespace rv = std::views; namespace rs = std::ranges; #endif // https://codeforces.com/blog/entry/96344 #pragma GCC optimize("O2,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") using namespace std; using i32 = int32_t; using u32 = uint32_t; using i64 = int64_t; using u64 = uint64_t; using f64 = double; using f128 = long double; #if __cplusplus >= 202002L template constexpr T MIN = std::numeric_limits::min(); template constexpr T MAX = std::numeric_limits::max(); template [[nodiscard]] static T sc(auto&& x) { return static_cast(x); } template [[nodiscard]] static T sz(auto&& x) { return static_cast(x.size()); } #endif static void NO() { std::cout << "NO\n"; } static void YES() { std::cout << "YES\n"; } template using vec = std::vector; #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() #define ff first #define ss second #ifdef LOCAL #define db(...) std::print(__VA_ARGS__) #define dbln(...) std::println(__VA_ARGS__) #else #define db(...) #define dbln(...) #endif // }}} void solve() { u32 n, m; cin >> n >> m; // -1/0/1 -> unset, c0, c1 vector color(n + 1, -1); vec> forest(n + 1); for (u32 i = 0; i < m; ++i) { u32 u, v; cin >> u >> v; forest[u].push_back(v); forest[v].push_back(u); } auto bfs = [&](u32 u) -> bool { queue q{{u}}; color[u] = 0; while (!q.empty()) { u = q.front(); q.pop(); for (auto v : forest[u]) { if (color[v] == color[u]) { return false; } if (color[v] == -1) { color[v] = 1 - color[u]; q.push(v); } } } return true; }; for (u32 u = 1; u <= n; ++u) { if (color[u] == -1 && !bfs(u)) { cout << "IMPOSSIBLE\n"; return; } } for (u32 i = 1; i <= n; ++i) { cout << color[i] + 1 << " \n"[i == n]; } } int main() { // {{{ std::cin.exceptions(std::cin.failbit); #ifdef LOCAL std::cerr.rdbuf(std::cout.rdbuf()); std::cout.setf(std::ios::unitbuf); std::cerr.setf(std::ios::unitbuf); #else std::cin.tie(nullptr)->sync_with_stdio(false); #endif u32 tc = 1; // std::cin >> tc; for (u32 t = 0; t < tc; ++t) { solve(); } return 0; } // }}}