// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
using namespace std;
#define nl '\n'
#define pb push_back
#define sz(x) int(x.size())
template<class T> using V = vector<T>;
using vi = V<int>;
int main() {
cin.tie(0)->sync_with_stdio(0);
int N, M; cin >> N >> M;
V<vi> adj(N); vi in(N), path(N);
for(int i = 0; i < N - 1; i++) {
int u, v; cin >> u >> v; --u, --v;
adj[u].pb(v);
adj[v].pb(u);
in[u]++, in[v]++;
}
if (N == 1) {
cout << "YES" << nl;
cout << 1 << nl;
cout << 1 << nl;
exit(0-0);
}
if (N == 2) {
cout << "YES" << nl;
cout << 2 << nl;
cout << 1 << " " << 1 << nl;
exit(0-0);
}
if (M != N - 1) {
cout << "NO" << nl;
exit(0-0);
}
for(int u = 0; u < N; u++) if (in[u] == 1) {
for(auto& v : adj[u]) path[v] = 1;
}
for(int u = 0; u < N; u++) if (!path[u]) {
for(auto& v : adj[u]) in[v]--;
}
vi ans;
function<void(int)> dfs = [&](int u) {
ans.pb(u); path[u] = 0;
int chd = 0;
for(auto& v : adj[u]) if (path[v]) {
dfs(v); chd++;
}
if (chd >= 2) {
cout << "NO" << nl;
exit(0-0);
}
ans.pb(u);
};
for(int u = 0; u < N; u++) if (path[u] && in[u] <= 1) dfs(u);
if (sz(ans) == 0) {
ans.pb(0); ans.pb(0);
}
cout << "YES" << nl;
cout << sz(ans) << nl;
for(auto& x : ans) cout << x + 1 << " ";
cout << nl;
exit(0-0);
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
1 ms |
344 KB |
Output is correct |
3 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
4 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
5 |
Correct |
1 ms |
344 KB |
Output is correct |
6 |
Correct |
1 ms |
344 KB |
Output is correct |
7 |
Correct |
1 ms |
344 KB |
Output is correct |
8 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
9 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
10 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
344 KB |
Output is correct |
3 |
Correct |
1 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
6 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
7 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
8 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
9 |
Partially correct |
0 ms |
348 KB |
Failed to provide a successful strategy. |
10 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
11 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
12 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
13 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
14 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
15 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
16 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
17 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
18 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
19 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
20 |
Partially correct |
1 ms |
348 KB |
Failed to provide a successful strategy. |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
1 ms |
344 KB |
Output is correct |
3 |
Partially correct |
1 ms |
344 KB |
Failed to provide a successful strategy. |
4 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
5 |
Correct |
1 ms |
344 KB |
Output is correct |
6 |
Correct |
1 ms |
344 KB |
Output is correct |
7 |
Correct |
1 ms |
344 KB |
Output is correct |
8 |
Partially correct |
0 ms |
344 KB |
Failed to provide a successful strategy. |
9 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
10 |
Halted |
0 ms |
0 KB |
- |