#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
#define all(x) (x).begin(),(x).end()
#define X first
#define Y second
#define sep ' '
#define endl '\n'
#define debug(x) cerr << #x << ": " << x << endl;
const ll MAXN = 1e3 + 10;
int n, m, dist[MAXN], par[MAXN], D[MAXN];
vector<int> adj[MAXN], diam, ans;
void dfs(int v) {
dist[v] = dist[par[v]] + 1;
D[v] = 1;
for (int u : adj[v]) {
if (u != par[v]) {
par[u] = v;
dfs(u);
D[v] = max(D[v], D[u] + 1);
}
}
}
inline void add(int v) {
int m = ans.size();
if (m >= 2 && ans[m - 1] == v && ans[m - 2] == v) {
ans.pop_back();
ans.pop_back();
}
ans.push_back(v);
}
inline void dojob() {
int m = diam.size();
diam.push_back(-1);
int i = 0;
for (i = 0; i < m; i++) {
int v = diam[i];
add(v);
for (int u : adj[v]) {
if (u == par[v] || u == diam[i + 1]) continue;
if (D[u] >= 2) {
cout << "NO" << endl;
exit(0);
}
add(u);
add(v);
}
}
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> n >> m;
if (m >= n) return cout << "NO" << endl, 0;
if (n == 1) return cout << "YES" << endl << 1 << endl << 1 << endl, 0;
if (n == 2) return cout << "YES" << endl << 2 << endl << 1 << sep << 1 << endl, 0;
for (int i = 1; i <= m; i++) {
int u, v;
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
int rt = 0;
vector<int> vec;
for (int i = 1; i <= n; i++) {
if (adj[i].size() == 1)
vec.push_back(i);
else rt = i;
}
for (int e : vec)
for (int u : adj[e])
adj[u].erase(find(all(adj[u]), e));
dfs(rt);
int v = max_element(dist, dist + MAXN) - dist;
memset(par, 0, sizeof par);
memset(dist, 0, sizeof dist);
dfs(v);
v = max_element(dist, dist + MAXN) - dist;
while (v) {
diam.push_back(v);
v = par[v];
}
reverse(all(diam));
dojob();
int m = ans.size();
while (m--) ans.push_back(ans[m]);
cout << "YES" << endl << ans.size() << endl;
for (int e : ans) cout << e << sep;
cout << endl;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
0 ms |
340 KB |
Output is correct |
5 |
Correct |
0 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
340 KB |
Output is correct |
8 |
Correct |
0 ms |
340 KB |
Output is correct |
9 |
Correct |
0 ms |
340 KB |
Output is correct |
10 |
Correct |
0 ms |
340 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
0 ms |
340 KB |
Output is correct |
13 |
Correct |
0 ms |
340 KB |
Output is correct |
14 |
Correct |
0 ms |
340 KB |
Output is correct |
15 |
Correct |
0 ms |
340 KB |
Output is correct |
16 |
Correct |
0 ms |
340 KB |
Output is correct |
17 |
Correct |
0 ms |
340 KB |
Output is correct |
18 |
Correct |
1 ms |
340 KB |
Output is correct |
19 |
Correct |
0 ms |
340 KB |
Output is correct |
20 |
Correct |
0 ms |
340 KB |
Output is correct |
21 |
Correct |
1 ms |
340 KB |
Output is correct |
22 |
Correct |
0 ms |
340 KB |
Output is correct |
23 |
Correct |
0 ms |
340 KB |
Output is correct |
24 |
Correct |
0 ms |
340 KB |
Output is correct |
25 |
Correct |
0 ms |
340 KB |
Output is correct |
26 |
Correct |
0 ms |
340 KB |
Output is correct |
27 |
Correct |
0 ms |
340 KB |
Output is correct |
28 |
Correct |
0 ms |
340 KB |
Output is correct |
29 |
Correct |
0 ms |
340 KB |
Output is correct |
30 |
Correct |
0 ms |
340 KB |
Output is correct |
31 |
Correct |
0 ms |
340 KB |
Output is correct |
32 |
Correct |
0 ms |
340 KB |
Output is correct |
33 |
Correct |
1 ms |
340 KB |
Output is correct |
34 |
Correct |
0 ms |
340 KB |
Output is correct |
35 |
Correct |
0 ms |
340 KB |
Output is correct |
36 |
Correct |
1 ms |
340 KB |
Output is correct |
37 |
Correct |
0 ms |
340 KB |
Output is correct |
38 |
Correct |
1 ms |
340 KB |
Output is correct |
39 |
Correct |
0 ms |
340 KB |
Output is correct |
40 |
Correct |
0 ms |
340 KB |
Output is correct |
41 |
Correct |
0 ms |
340 KB |
Output is correct |
42 |
Correct |
1 ms |
340 KB |
Output is correct |
43 |
Correct |
1 ms |
340 KB |
Output is correct |
44 |
Correct |
0 ms |
340 KB |
Output is correct |
45 |
Correct |
0 ms |
340 KB |
Output is correct |
46 |
Correct |
0 ms |
340 KB |
Output is correct |
47 |
Correct |
0 ms |
340 KB |
Output is correct |
48 |
Correct |
1 ms |
340 KB |
Output is correct |
49 |
Correct |
0 ms |
340 KB |
Output is correct |
50 |
Correct |
0 ms |
340 KB |
Output is correct |
51 |
Correct |
1 ms |
340 KB |
Output is correct |
52 |
Correct |
0 ms |
340 KB |
Output is correct |
53 |
Correct |
1 ms |
340 KB |
Output is correct |
54 |
Correct |
0 ms |
340 KB |
Output is correct |
55 |
Correct |
0 ms |
340 KB |
Output is correct |
56 |
Correct |
0 ms |
340 KB |
Output is correct |
57 |
Correct |
1 ms |
340 KB |
Output is correct |
58 |
Correct |
0 ms |
340 KB |
Output is correct |
59 |
Correct |
0 ms |
340 KB |
Output is correct |
60 |
Correct |
1 ms |
352 KB |
Output is correct |
61 |
Correct |
0 ms |
340 KB |
Output is correct |
62 |
Correct |
1 ms |
340 KB |
Output is correct |
63 |
Correct |
0 ms |
340 KB |
Output is correct |
64 |
Correct |
0 ms |
340 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
0 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
1 ms |
340 KB |
Output is correct |
8 |
Correct |
0 ms |
340 KB |
Output is correct |
9 |
Correct |
0 ms |
340 KB |
Output is correct |
10 |
Correct |
1 ms |
340 KB |
Output is correct |
11 |
Correct |
1 ms |
468 KB |
Output is correct |
12 |
Correct |
1 ms |
340 KB |
Output is correct |
13 |
Correct |
1 ms |
340 KB |
Output is correct |
14 |
Correct |
1 ms |
340 KB |
Output is correct |
15 |
Correct |
1 ms |
340 KB |
Output is correct |
16 |
Correct |
1 ms |
468 KB |
Output is correct |
17 |
Correct |
1 ms |
468 KB |
Output is correct |
18 |
Correct |
1 ms |
468 KB |
Output is correct |
19 |
Correct |
1 ms |
468 KB |
Output is correct |
20 |
Correct |
1 ms |
468 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
0 ms |
340 KB |
Output is correct |
5 |
Correct |
0 ms |
340 KB |
Output is correct |
6 |
Correct |
1 ms |
340 KB |
Output is correct |
7 |
Correct |
0 ms |
340 KB |
Output is correct |
8 |
Correct |
0 ms |
340 KB |
Output is correct |
9 |
Correct |
0 ms |
340 KB |
Output is correct |
10 |
Correct |
0 ms |
340 KB |
Output is correct |
11 |
Correct |
0 ms |
340 KB |
Output is correct |
12 |
Correct |
0 ms |
340 KB |
Output is correct |
13 |
Correct |
0 ms |
340 KB |
Output is correct |
14 |
Correct |
0 ms |
340 KB |
Output is correct |
15 |
Correct |
0 ms |
340 KB |
Output is correct |
16 |
Correct |
0 ms |
340 KB |
Output is correct |
17 |
Correct |
0 ms |
340 KB |
Output is correct |
18 |
Correct |
1 ms |
340 KB |
Output is correct |
19 |
Correct |
0 ms |
340 KB |
Output is correct |
20 |
Correct |
0 ms |
340 KB |
Output is correct |
21 |
Correct |
1 ms |
340 KB |
Output is correct |
22 |
Correct |
0 ms |
340 KB |
Output is correct |
23 |
Correct |
0 ms |
340 KB |
Output is correct |
24 |
Correct |
0 ms |
340 KB |
Output is correct |
25 |
Correct |
0 ms |
340 KB |
Output is correct |
26 |
Correct |
0 ms |
340 KB |
Output is correct |
27 |
Correct |
0 ms |
340 KB |
Output is correct |
28 |
Correct |
0 ms |
340 KB |
Output is correct |
29 |
Correct |
0 ms |
340 KB |
Output is correct |
30 |
Correct |
0 ms |
340 KB |
Output is correct |
31 |
Correct |
0 ms |
340 KB |
Output is correct |
32 |
Correct |
0 ms |
340 KB |
Output is correct |
33 |
Correct |
1 ms |
340 KB |
Output is correct |
34 |
Correct |
0 ms |
340 KB |
Output is correct |
35 |
Correct |
0 ms |
340 KB |
Output is correct |
36 |
Correct |
1 ms |
340 KB |
Output is correct |
37 |
Correct |
0 ms |
340 KB |
Output is correct |
38 |
Correct |
1 ms |
340 KB |
Output is correct |
39 |
Correct |
0 ms |
340 KB |
Output is correct |
40 |
Correct |
0 ms |
340 KB |
Output is correct |
41 |
Correct |
0 ms |
340 KB |
Output is correct |
42 |
Correct |
1 ms |
340 KB |
Output is correct |
43 |
Correct |
1 ms |
340 KB |
Output is correct |
44 |
Correct |
0 ms |
340 KB |
Output is correct |
45 |
Correct |
0 ms |
340 KB |
Output is correct |
46 |
Correct |
0 ms |
340 KB |
Output is correct |
47 |
Correct |
0 ms |
340 KB |
Output is correct |
48 |
Correct |
1 ms |
340 KB |
Output is correct |
49 |
Correct |
0 ms |
340 KB |
Output is correct |
50 |
Correct |
0 ms |
340 KB |
Output is correct |
51 |
Correct |
1 ms |
340 KB |
Output is correct |
52 |
Correct |
0 ms |
340 KB |
Output is correct |
53 |
Correct |
1 ms |
340 KB |
Output is correct |
54 |
Correct |
0 ms |
340 KB |
Output is correct |
55 |
Correct |
0 ms |
340 KB |
Output is correct |
56 |
Correct |
0 ms |
340 KB |
Output is correct |
57 |
Correct |
1 ms |
340 KB |
Output is correct |
58 |
Correct |
0 ms |
340 KB |
Output is correct |
59 |
Correct |
0 ms |
340 KB |
Output is correct |
60 |
Correct |
1 ms |
352 KB |
Output is correct |
61 |
Correct |
0 ms |
340 KB |
Output is correct |
62 |
Correct |
1 ms |
340 KB |
Output is correct |
63 |
Correct |
0 ms |
340 KB |
Output is correct |
64 |
Correct |
0 ms |
340 KB |
Output is correct |
65 |
Correct |
0 ms |
340 KB |
Output is correct |
66 |
Correct |
0 ms |
340 KB |
Output is correct |
67 |
Correct |
0 ms |
340 KB |
Output is correct |
68 |
Correct |
0 ms |
340 KB |
Output is correct |
69 |
Correct |
0 ms |
340 KB |
Output is correct |
70 |
Correct |
0 ms |
340 KB |
Output is correct |
71 |
Correct |
0 ms |
340 KB |
Output is correct |
72 |
Correct |
0 ms |
340 KB |
Output is correct |
73 |
Correct |
0 ms |
340 KB |
Output is correct |
74 |
Correct |
0 ms |
340 KB |
Output is correct |
75 |
Correct |
0 ms |
340 KB |
Output is correct |
76 |
Correct |
1 ms |
340 KB |
Output is correct |
77 |
Correct |
1 ms |
340 KB |
Output is correct |
78 |
Correct |
0 ms |
340 KB |
Output is correct |
79 |
Correct |
1 ms |
340 KB |
Output is correct |
80 |
Correct |
1 ms |
340 KB |
Output is correct |
81 |
Correct |
1 ms |
340 KB |
Output is correct |
82 |
Correct |
1 ms |
340 KB |
Output is correct |
83 |
Correct |
1 ms |
340 KB |
Output is correct |
84 |
Correct |
1 ms |
340 KB |
Output is correct |
85 |
Correct |
1 ms |
340 KB |
Output is correct |
86 |
Correct |
1 ms |
340 KB |
Output is correct |
87 |
Correct |
1 ms |
340 KB |
Output is correct |
88 |
Correct |
1 ms |
340 KB |
Output is correct |
89 |
Correct |
1 ms |
340 KB |
Output is correct |
90 |
Correct |
1 ms |
340 KB |
Output is correct |
91 |
Correct |
1 ms |
400 KB |
Output is correct |
92 |
Correct |
1 ms |
340 KB |
Output is correct |
93 |
Correct |
1 ms |
340 KB |
Output is correct |
94 |
Correct |
1 ms |
340 KB |
Output is correct |
95 |
Correct |
1 ms |
340 KB |
Output is correct |
96 |
Correct |
1 ms |
340 KB |
Output is correct |
97 |
Correct |
1 ms |
340 KB |
Output is correct |
98 |
Correct |
1 ms |
340 KB |
Output is correct |
99 |
Correct |
1 ms |
340 KB |
Output is correct |
100 |
Correct |
1 ms |
340 KB |
Output is correct |
101 |
Correct |
1 ms |
340 KB |
Output is correct |
102 |
Correct |
1 ms |
340 KB |
Output is correct |
103 |
Correct |
1 ms |
340 KB |
Output is correct |
104 |
Correct |
1 ms |
340 KB |
Output is correct |
105 |
Correct |
1 ms |
340 KB |
Output is correct |
106 |
Correct |
1 ms |
340 KB |
Output is correct |
107 |
Correct |
1 ms |
340 KB |
Output is correct |
108 |
Correct |
1 ms |
340 KB |
Output is correct |
109 |
Correct |
1 ms |
340 KB |
Output is correct |
110 |
Correct |
1 ms |
340 KB |
Output is correct |
111 |
Correct |
1 ms |
340 KB |
Output is correct |
112 |
Correct |
1 ms |
340 KB |
Output is correct |
113 |
Correct |
1 ms |
340 KB |
Output is correct |
114 |
Correct |
1 ms |
340 KB |
Output is correct |
115 |
Correct |
1 ms |
340 KB |
Output is correct |
116 |
Correct |
1 ms |
340 KB |
Output is correct |
117 |
Correct |
1 ms |
340 KB |
Output is correct |
118 |
Correct |
1 ms |
340 KB |
Output is correct |
119 |
Correct |
1 ms |
340 KB |
Output is correct |
120 |
Correct |
1 ms |
340 KB |
Output is correct |
121 |
Correct |
1 ms |
340 KB |
Output is correct |
122 |
Correct |
1 ms |
340 KB |
Output is correct |
123 |
Correct |
1 ms |
340 KB |
Output is correct |
124 |
Correct |
1 ms |
340 KB |
Output is correct |
125 |
Correct |
1 ms |
340 KB |
Output is correct |
126 |
Correct |
1 ms |
340 KB |
Output is correct |
127 |
Correct |
1 ms |
340 KB |
Output is correct |
128 |
Correct |
1 ms |
340 KB |
Output is correct |
129 |
Correct |
1 ms |
340 KB |
Output is correct |
130 |
Correct |
1 ms |
340 KB |
Output is correct |
131 |
Correct |
1 ms |
340 KB |
Output is correct |
132 |
Correct |
1 ms |
340 KB |
Output is correct |
133 |
Correct |
1 ms |
340 KB |
Output is correct |
134 |
Correct |
0 ms |
340 KB |
Output is correct |
135 |
Correct |
1 ms |
340 KB |
Output is correct |
136 |
Correct |
0 ms |
340 KB |
Output is correct |
137 |
Correct |
0 ms |
340 KB |
Output is correct |
138 |
Correct |
0 ms |
340 KB |
Output is correct |
139 |
Correct |
0 ms |
340 KB |
Output is correct |
140 |
Correct |
0 ms |
340 KB |
Output is correct |
141 |
Correct |
1 ms |
340 KB |
Output is correct |
142 |
Correct |
0 ms |
340 KB |
Output is correct |
143 |
Correct |
0 ms |
340 KB |
Output is correct |
144 |
Correct |
1 ms |
468 KB |
Output is correct |
145 |
Correct |
1 ms |
468 KB |
Output is correct |