#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define REP(i, n) FOR(i, 0, n)
#define ll long long
using namespace std;
const int MAXN = 1010;
vector <int> ve[MAXN];
int bio[MAXN];
void impossible() {
cout << "NO\n";
exit(0);
}
void dfs(int x, int par) {
bio[x] = bio[par] + 1;
for (int y : ve[x]) {
if (y == par) continue;
if (bio[y]) impossible();
dfs(y, x);
}
return;
}
int main_path[MAXN];
vector <int> path;
int twig[MAXN];
int rek(int x, int par) {
int ma = 0;
for (int y : ve[x]) {
if (y == par) continue;
if (main_path[y]) continue;
ma = max(ma, rek(y, x));
}
if (ma == 3) impossible();
twig[x] = ma;
return ma + 1;
}
vector <int> out;
void print() {
cout << "YES\n";
cout << out.size() << "\n";
for (int x : out) cout << x + 1 << " ";
cout << "\n";
return;
}
int main() {
int n, m;
cin >> n >> m;
if (n == 1) {
out.push_back(0);
print();
return 0;
}
if (n == 2) {
out.push_back(0);
out.push_back(0);
print();
return 0;
}
REP(i, m) {
int a, b;
cin >> a >> b;
a--, b--;
ve[a].push_back(b);
ve[b].push_back(a);
}
dfs(0, 0);
int A = -1, dist = -1;
REP(i, n) {
if (bio[i] > dist) {
dist = bio[i];
A = i;
}
}
memset(bio, 0, sizeof bio);
dfs(A, A);
int B = -1;
dist = -1;
REP(i, n) {
if (bio[i] > dist) {
dist = bio[i];
B = i;
}
}
int x = B;
while (x != A) {
main_path[x] = 1;
path.push_back(x);
for (int y : ve[x]) {
if (bio[y] == bio[x] - 1) {
x = y;
break;
}
}
}
path.push_back(A);
main_path[A] = 1;
memset(twig, 0, sizeof twig);
REP(i, n) {
if (main_path[i]) twig[i] = rek(i, i) - 1;
}
// remove first and last node of path to optimise
if (path.size() > 1) {
main_path[path[0]] = 0;
path.erase(path.begin());
twig[path[0]] = max(twig[path[0]], 1);
}
reverse(path.begin(), path.end());
if (path.size() > 1) {
main_path[path[0]] = 0;
path.erase(path.begin());
twig[path[0]] = max(twig[path[0]], 1);
}
for (int x : path) {
out.push_back(x);
if (twig[x] == 2) {
for (int y : ve[x]) {
if (main_path[y] || twig[y] == 0) continue;
out.push_back(y);
out.push_back(x);
}
}
}
reverse(path.begin(), path.end());
for (int x : path) {
out.push_back(x);
if (twig[x] == 2) {
for (int y : ve[x]) {
if (main_path[y] || twig[y] == 0) continue;
out.push_back(y);
out.push_back(x);
}
}
}
print();
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
220 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
204 KB |
Output is correct |
16 |
Correct |
1 ms |
204 KB |
Output is correct |
17 |
Correct |
0 ms |
204 KB |
Output is correct |
18 |
Correct |
0 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
204 KB |
Output is correct |
20 |
Correct |
1 ms |
204 KB |
Output is correct |
21 |
Correct |
1 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
204 KB |
Output is correct |
23 |
Correct |
0 ms |
204 KB |
Output is correct |
24 |
Correct |
1 ms |
204 KB |
Output is correct |
25 |
Correct |
0 ms |
204 KB |
Output is correct |
26 |
Correct |
1 ms |
204 KB |
Output is correct |
27 |
Correct |
0 ms |
204 KB |
Output is correct |
28 |
Correct |
0 ms |
204 KB |
Output is correct |
29 |
Correct |
0 ms |
204 KB |
Output is correct |
30 |
Correct |
1 ms |
204 KB |
Output is correct |
31 |
Correct |
0 ms |
332 KB |
Output is correct |
32 |
Correct |
1 ms |
204 KB |
Output is correct |
33 |
Correct |
0 ms |
204 KB |
Output is correct |
34 |
Correct |
1 ms |
204 KB |
Output is correct |
35 |
Correct |
1 ms |
204 KB |
Output is correct |
36 |
Correct |
1 ms |
204 KB |
Output is correct |
37 |
Correct |
0 ms |
204 KB |
Output is correct |
38 |
Correct |
1 ms |
204 KB |
Output is correct |
39 |
Correct |
1 ms |
204 KB |
Output is correct |
40 |
Correct |
0 ms |
204 KB |
Output is correct |
41 |
Correct |
1 ms |
204 KB |
Output is correct |
42 |
Correct |
0 ms |
204 KB |
Output is correct |
43 |
Correct |
0 ms |
204 KB |
Output is correct |
44 |
Correct |
0 ms |
204 KB |
Output is correct |
45 |
Correct |
0 ms |
204 KB |
Output is correct |
46 |
Correct |
1 ms |
204 KB |
Output is correct |
47 |
Correct |
0 ms |
204 KB |
Output is correct |
48 |
Correct |
1 ms |
204 KB |
Output is correct |
49 |
Correct |
0 ms |
204 KB |
Output is correct |
50 |
Correct |
0 ms |
204 KB |
Output is correct |
51 |
Correct |
0 ms |
332 KB |
Output is correct |
52 |
Correct |
0 ms |
204 KB |
Output is correct |
53 |
Correct |
0 ms |
204 KB |
Output is correct |
54 |
Correct |
1 ms |
204 KB |
Output is correct |
55 |
Correct |
0 ms |
204 KB |
Output is correct |
56 |
Correct |
0 ms |
204 KB |
Output is correct |
57 |
Correct |
0 ms |
204 KB |
Output is correct |
58 |
Correct |
0 ms |
204 KB |
Output is correct |
59 |
Correct |
1 ms |
332 KB |
Output is correct |
60 |
Correct |
1 ms |
204 KB |
Output is correct |
61 |
Correct |
1 ms |
204 KB |
Output is correct |
62 |
Correct |
0 ms |
204 KB |
Output is correct |
63 |
Correct |
1 ms |
332 KB |
Output is correct |
64 |
Correct |
0 ms |
332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
320 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
1 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
1 ms |
332 KB |
Output is correct |
10 |
Correct |
1 ms |
324 KB |
Output is correct |
11 |
Correct |
2 ms |
332 KB |
Output is correct |
12 |
Correct |
2 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
332 KB |
Output is correct |
14 |
Correct |
1 ms |
332 KB |
Output is correct |
15 |
Correct |
1 ms |
332 KB |
Output is correct |
16 |
Correct |
2 ms |
332 KB |
Output is correct |
17 |
Correct |
1 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
332 KB |
Output is correct |
19 |
Correct |
1 ms |
332 KB |
Output is correct |
20 |
Correct |
1 ms |
332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
220 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
1 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
204 KB |
Output is correct |
16 |
Correct |
1 ms |
204 KB |
Output is correct |
17 |
Correct |
0 ms |
204 KB |
Output is correct |
18 |
Correct |
0 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
204 KB |
Output is correct |
20 |
Correct |
1 ms |
204 KB |
Output is correct |
21 |
Correct |
1 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
204 KB |
Output is correct |
23 |
Correct |
0 ms |
204 KB |
Output is correct |
24 |
Correct |
1 ms |
204 KB |
Output is correct |
25 |
Correct |
0 ms |
204 KB |
Output is correct |
26 |
Correct |
1 ms |
204 KB |
Output is correct |
27 |
Correct |
0 ms |
204 KB |
Output is correct |
28 |
Correct |
0 ms |
204 KB |
Output is correct |
29 |
Correct |
0 ms |
204 KB |
Output is correct |
30 |
Correct |
1 ms |
204 KB |
Output is correct |
31 |
Correct |
0 ms |
332 KB |
Output is correct |
32 |
Correct |
1 ms |
204 KB |
Output is correct |
33 |
Correct |
0 ms |
204 KB |
Output is correct |
34 |
Correct |
1 ms |
204 KB |
Output is correct |
35 |
Correct |
1 ms |
204 KB |
Output is correct |
36 |
Correct |
1 ms |
204 KB |
Output is correct |
37 |
Correct |
0 ms |
204 KB |
Output is correct |
38 |
Correct |
1 ms |
204 KB |
Output is correct |
39 |
Correct |
1 ms |
204 KB |
Output is correct |
40 |
Correct |
0 ms |
204 KB |
Output is correct |
41 |
Correct |
1 ms |
204 KB |
Output is correct |
42 |
Correct |
0 ms |
204 KB |
Output is correct |
43 |
Correct |
0 ms |
204 KB |
Output is correct |
44 |
Correct |
0 ms |
204 KB |
Output is correct |
45 |
Correct |
0 ms |
204 KB |
Output is correct |
46 |
Correct |
1 ms |
204 KB |
Output is correct |
47 |
Correct |
0 ms |
204 KB |
Output is correct |
48 |
Correct |
1 ms |
204 KB |
Output is correct |
49 |
Correct |
0 ms |
204 KB |
Output is correct |
50 |
Correct |
0 ms |
204 KB |
Output is correct |
51 |
Correct |
0 ms |
332 KB |
Output is correct |
52 |
Correct |
0 ms |
204 KB |
Output is correct |
53 |
Correct |
0 ms |
204 KB |
Output is correct |
54 |
Correct |
1 ms |
204 KB |
Output is correct |
55 |
Correct |
0 ms |
204 KB |
Output is correct |
56 |
Correct |
0 ms |
204 KB |
Output is correct |
57 |
Correct |
0 ms |
204 KB |
Output is correct |
58 |
Correct |
0 ms |
204 KB |
Output is correct |
59 |
Correct |
1 ms |
332 KB |
Output is correct |
60 |
Correct |
1 ms |
204 KB |
Output is correct |
61 |
Correct |
1 ms |
204 KB |
Output is correct |
62 |
Correct |
0 ms |
204 KB |
Output is correct |
63 |
Correct |
1 ms |
332 KB |
Output is correct |
64 |
Correct |
0 ms |
332 KB |
Output is correct |
65 |
Correct |
0 ms |
204 KB |
Output is correct |
66 |
Correct |
1 ms |
204 KB |
Output is correct |
67 |
Correct |
1 ms |
204 KB |
Output is correct |
68 |
Correct |
0 ms |
204 KB |
Output is correct |
69 |
Correct |
0 ms |
204 KB |
Output is correct |
70 |
Correct |
0 ms |
332 KB |
Output is correct |
71 |
Correct |
0 ms |
204 KB |
Output is correct |
72 |
Correct |
1 ms |
204 KB |
Output is correct |
73 |
Correct |
0 ms |
204 KB |
Output is correct |
74 |
Correct |
0 ms |
204 KB |
Output is correct |
75 |
Correct |
0 ms |
332 KB |
Output is correct |
76 |
Correct |
1 ms |
204 KB |
Output is correct |
77 |
Correct |
0 ms |
204 KB |
Output is correct |
78 |
Correct |
0 ms |
204 KB |
Output is correct |
79 |
Correct |
1 ms |
332 KB |
Output is correct |
80 |
Correct |
1 ms |
332 KB |
Output is correct |
81 |
Correct |
1 ms |
332 KB |
Output is correct |
82 |
Correct |
1 ms |
332 KB |
Output is correct |
83 |
Correct |
1 ms |
332 KB |
Output is correct |
84 |
Correct |
1 ms |
332 KB |
Output is correct |
85 |
Correct |
1 ms |
332 KB |
Output is correct |
86 |
Correct |
1 ms |
332 KB |
Output is correct |
87 |
Correct |
1 ms |
336 KB |
Output is correct |
88 |
Correct |
1 ms |
332 KB |
Output is correct |
89 |
Correct |
2 ms |
332 KB |
Output is correct |
90 |
Correct |
1 ms |
332 KB |
Output is correct |
91 |
Correct |
1 ms |
332 KB |
Output is correct |
92 |
Correct |
1 ms |
332 KB |
Output is correct |
93 |
Correct |
1 ms |
332 KB |
Output is correct |
94 |
Correct |
1 ms |
332 KB |
Output is correct |
95 |
Correct |
1 ms |
332 KB |
Output is correct |
96 |
Correct |
1 ms |
332 KB |
Output is correct |
97 |
Correct |
1 ms |
332 KB |
Output is correct |
98 |
Correct |
1 ms |
332 KB |
Output is correct |
99 |
Correct |
1 ms |
332 KB |
Output is correct |
100 |
Correct |
1 ms |
344 KB |
Output is correct |
101 |
Correct |
1 ms |
332 KB |
Output is correct |
102 |
Correct |
1 ms |
332 KB |
Output is correct |
103 |
Correct |
1 ms |
332 KB |
Output is correct |
104 |
Correct |
1 ms |
332 KB |
Output is correct |
105 |
Correct |
1 ms |
332 KB |
Output is correct |
106 |
Correct |
2 ms |
332 KB |
Output is correct |
107 |
Correct |
2 ms |
332 KB |
Output is correct |
108 |
Correct |
1 ms |
332 KB |
Output is correct |
109 |
Correct |
1 ms |
336 KB |
Output is correct |
110 |
Correct |
1 ms |
332 KB |
Output is correct |
111 |
Correct |
1 ms |
332 KB |
Output is correct |
112 |
Correct |
1 ms |
332 KB |
Output is correct |
113 |
Correct |
2 ms |
352 KB |
Output is correct |
114 |
Correct |
1 ms |
336 KB |
Output is correct |
115 |
Correct |
1 ms |
332 KB |
Output is correct |
116 |
Correct |
1 ms |
332 KB |
Output is correct |
117 |
Correct |
1 ms |
332 KB |
Output is correct |
118 |
Correct |
1 ms |
332 KB |
Output is correct |
119 |
Correct |
1 ms |
332 KB |
Output is correct |
120 |
Correct |
1 ms |
332 KB |
Output is correct |
121 |
Correct |
1 ms |
332 KB |
Output is correct |
122 |
Correct |
1 ms |
332 KB |
Output is correct |
123 |
Correct |
1 ms |
332 KB |
Output is correct |
124 |
Correct |
1 ms |
332 KB |
Output is correct |
125 |
Correct |
1 ms |
332 KB |
Output is correct |
126 |
Correct |
1 ms |
332 KB |
Output is correct |
127 |
Correct |
1 ms |
332 KB |
Output is correct |
128 |
Correct |
1 ms |
332 KB |
Output is correct |
129 |
Correct |
1 ms |
332 KB |
Output is correct |
130 |
Correct |
1 ms |
332 KB |
Output is correct |
131 |
Correct |
1 ms |
332 KB |
Output is correct |
132 |
Correct |
1 ms |
332 KB |
Output is correct |
133 |
Correct |
1 ms |
332 KB |
Output is correct |
134 |
Correct |
56 ms |
1868 KB |
Output is correct |
135 |
Correct |
41 ms |
1864 KB |
Output is correct |
136 |
Correct |
111 ms |
5388 KB |
Output is correct |
137 |
Correct |
74 ms |
3240 KB |
Output is correct |
138 |
Correct |
129 ms |
4592 KB |
Output is correct |
139 |
Correct |
239 ms |
7868 KB |
Output is correct |
140 |
Correct |
31 ms |
1348 KB |
Output is correct |
141 |
Correct |
11 ms |
604 KB |
Output is correct |
142 |
Correct |
212 ms |
7452 KB |
Output is correct |
143 |
Correct |
254 ms |
8228 KB |
Output is correct |
144 |
Correct |
1 ms |
332 KB |
Output is correct |
145 |
Correct |
1 ms |
332 KB |
Output is correct |