137 lines
2.4 KiB
C++
137 lines
2.4 KiB
C++
#include <bits/stdc++.h> // {{{
|
|
|
|
#include <version>
|
|
#ifdef __cpp_lib_ranges_enumerate
|
|
#include <ranges>
|
|
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 <typename T>
|
|
constexpr T MIN = std::numeric_limits<T>::min();
|
|
|
|
template <typename T>
|
|
constexpr T MAX = std::numeric_limits<T>::max();
|
|
|
|
template <typename T>
|
|
[[nodiscard]] static T sc(auto&& x) {
|
|
return static_cast<T>(x);
|
|
}
|
|
|
|
template <typename T>
|
|
[[nodiscard]] static T sz(auto&& x) {
|
|
return static_cast<T>(x.size());
|
|
}
|
|
#endif
|
|
|
|
static void NO() {
|
|
std::cout << "NO\n";
|
|
}
|
|
|
|
static void YES() {
|
|
std::cout << "YES\n";
|
|
}
|
|
|
|
template <typename T>
|
|
using vec = std::vector<T>;
|
|
|
|
#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<i32> color(n + 1, -1);
|
|
|
|
vec<vec<u32>> 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<u32> 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;
|
|
}
|
|
// }}}
|