#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e3 + 25;
vector <int> adj[MAXN];
int n, m;
int cnt = 0;
void dfs (int pos, int par, int dep = 0) {
if (dep == 3) {
cnt++;
return;
}
for (auto j : adj[pos]) if (j != par) dfs(j, pos, dep + 1);
}
int main () {
cin >> n >> m;
bool flag = 1;
for (int i = 1; i <= m; i++) {
int a, b;
cin >> a >> b;
if (a > b) swap(a, b);
flag &= a + 1 == b;
adj[a].push_back(b);
adj[b].push_back(a);
}
if (m != n - 1) {
cout << "NO\n";
return 0;
}
if (flag) {
cout << "YES\n";
if (n == 1) {
cout << "1\n1\n";
return 0;
}
if (n == 2) {
cout << "2\n2 2\n";
return 0;
}
cout << 2 * (n - 2) << '\n';
for (int i = 2; i < n; i++) cout << i << " ";
for (int i = n - 1; i >= 2; i--) cout << i << " ";
cout << '\n';
return 0;
}
for (int i = 1; i <= n; i++) {
if (adj[i].size() >= 3) {
cnt = 0;
dfs(i, -1);
if (cnt >= 3) {
cout << "NO\n";
return 0;
}
}
}
cout << "YES\n";
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
344 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
1 ms |
348 KB |
Output is correct |
5 |
Incorrect |
1 ms |
348 KB |
Unexpected end of file - int32 expected |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
0 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
1 ms |
348 KB |
Output is correct |
12 |
Correct |
1 ms |
348 KB |
Output is correct |
13 |
Correct |
1 ms |
348 KB |
Output is correct |
14 |
Correct |
1 ms |
344 KB |
Output is correct |
15 |
Correct |
1 ms |
344 KB |
Output is correct |
16 |
Correct |
1 ms |
344 KB |
Output is correct |
17 |
Correct |
1 ms |
348 KB |
Output is correct |
18 |
Correct |
1 ms |
348 KB |
Output is correct |
19 |
Correct |
1 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
344 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
1 ms |
348 KB |
Output is correct |
5 |
Incorrect |
1 ms |
348 KB |
Unexpected end of file - int32 expected |
6 |
Halted |
0 ms |
0 KB |
- |