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Bipartite_Checking.cpp
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71 lines (62 loc) · 1.61 KB
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#include <bits/stdc++.h>
using namespace std;
void solve() {
int n, m;
cin >> n >> m;
vector<vector<int>> adj(n);
for (int i = 0; i < m; i++) {
int u, v;
cin >> u >> v;
u--, v--;
adj[u].push_back(v);
adj[v].push_back(u);
}
// Check an undirected graph is bipartite, O(n+m)
vector<int> color(n, -1);
vector<vector<int>> c(2);
auto is_bipartite = [&]() -> bool {
queue<int> q;
for (int i = 0; i < n; i++) {
if (color[i] == -1) {
color[i] = 0;
c[color[i]].push_back(i);
q.push(i);
while (!q.empty()) {
int v = q.front();
q.pop();
for (auto u : adj[v]) {
if (color[u] == -1) {
color[u] = color[v] ^ 1;
c[color[u]].push_back(u);
q.push(u);
} else if (color[u] == color[v]) {
return false;
}
}
}
}
}
return true;
};
if (is_bipartite()) {
cout << "YES\n";
for (auto v : c[0]) {
cout << v + 1 << " \n"[v == c[0].back()];
}
for (auto v : c[1]) {
cout << v + 1 << " \n"[v == c[1].back()];
}
} else {
cout << "NO\n";
}
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
//cin >> t;
while (t--) {
solve();
}
return 0;
}