#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define st first
#define nd second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
#define ll long long
ll mod=1000000007;
int inf=1000000007;
ll infl=1000000000000000007;
vector<int>G[1007];
int d[1007];
int h[1007];
int o[1007];
bool is[1007];
void dfs(int v)
{
h[v]=1;
for(auto u:G[v])
{
if(u==o[v]) continue;
o[u]=v;
d[u]=d[v]+1;
dfs(u);
h[v]=max(h[v],h[u]+1);
}
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n,m,a,b;
cin>>n>>m;
if(m!=n-1)
{
cout<<"NO";
return 0;
}
if(n<=2)
{
cout<<"YES"<<endl<<n<<endl<<1<<" ";
if(n==2) cout<<1;
return 0;
}
for(int i=0;i<n-1;i++)
{
cin>>a>>b;
G[a].pb(b);
G[b].pb(a);
}
for(int i=1;i<=n;i++)
{
o[i]=0;
dfs(i);
int c=0;
for(auto u:G[i]) if(h[u]>2) c++;
if(c>2)
{
cout<<"NO";
return 0;
}
}
cout<<"YES"<<endl;
o[1]=0;
d[1]=0;
dfs(1);
int mx=0,p1,p2;
for(int i=1;i<=n;i++)
{
if(d[i]>mx)
{
mx=d[i];
p1=i;
}
}
o[p1]=0;
d[p1]=0;
dfs(p1);
mx=0;
for(int i=1;i<=n;i++)
{
if(d[i]>mx)
{
mx=d[i];
p2=i;
}
}
vector<int>diam;
while(p2!=p1)
{
if(d[p2]!=mx) diam.pb(p2);
is[p2]=1;
p2=o[p2];
}
vector<int>vec,ans;
for(auto v:diam)
{
vec.pb(v);
for(auto u:G[v])
{
if(!is[u]&&sz(G[u])>1)
{
vec.pb(u);
vec.pb(v);
}
}
}
for(auto x:vec) ans.pb(x);
reverse(all(vec));
for(auto x:vec) ans.pb(x);
cout<<sz(ans)<<endl;
for(auto x:ans) cout<<x<<" ";
return 0;
}
Compilation message
newspapers.cpp: In function 'int main()':
newspapers.cpp:97:13: warning: 'p1' may be used uninitialized in this function [-Wmaybe-uninitialized]
97 | while(p2!=p1)
| ~~^~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
332 KB |
Output is correct |
8 |
Correct |
0 ms |
332 KB |
Output is correct |
9 |
Correct |
0 ms |
332 KB |
Output is correct |
10 |
Correct |
0 ms |
340 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 |
332 KB |
Output is correct |
14 |
Correct |
1 ms |
332 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
0 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
336 KB |
Output is correct |
20 |
Correct |
1 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
340 KB |
Output is correct |
22 |
Correct |
0 ms |
340 KB |
Output is correct |
23 |
Correct |
1 ms |
332 KB |
Output is correct |
24 |
Correct |
1 ms |
332 KB |
Output is correct |
25 |
Correct |
0 ms |
332 KB |
Output is correct |
26 |
Correct |
1 ms |
340 KB |
Output is correct |
27 |
Correct |
1 ms |
332 KB |
Output is correct |
28 |
Correct |
1 ms |
332 KB |
Output is correct |
29 |
Correct |
1 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
31 |
Correct |
0 ms |
332 KB |
Output is correct |
32 |
Correct |
0 ms |
332 KB |
Output is correct |
33 |
Correct |
0 ms |
332 KB |
Output is correct |
34 |
Correct |
1 ms |
340 KB |
Output is correct |
35 |
Correct |
1 ms |
332 KB |
Output is correct |
36 |
Correct |
1 ms |
332 KB |
Output is correct |
37 |
Correct |
0 ms |
332 KB |
Output is correct |
38 |
Correct |
0 ms |
332 KB |
Output is correct |
39 |
Correct |
1 ms |
340 KB |
Output is correct |
40 |
Correct |
1 ms |
332 KB |
Output is correct |
41 |
Correct |
0 ms |
332 KB |
Output is correct |
42 |
Correct |
0 ms |
332 KB |
Output is correct |
43 |
Correct |
0 ms |
332 KB |
Output is correct |
44 |
Correct |
0 ms |
332 KB |
Output is correct |
45 |
Correct |
1 ms |
332 KB |
Output is correct |
46 |
Correct |
1 ms |
340 KB |
Output is correct |
47 |
Correct |
1 ms |
332 KB |
Output is correct |
48 |
Correct |
1 ms |
332 KB |
Output is correct |
49 |
Correct |
0 ms |
332 KB |
Output is correct |
50 |
Correct |
1 ms |
340 KB |
Output is correct |
51 |
Correct |
0 ms |
332 KB |
Output is correct |
52 |
Correct |
0 ms |
332 KB |
Output is correct |
53 |
Correct |
0 ms |
340 KB |
Output is correct |
54 |
Correct |
0 ms |
332 KB |
Output is correct |
55 |
Correct |
1 ms |
332 KB |
Output is correct |
56 |
Correct |
1 ms |
332 KB |
Output is correct |
57 |
Correct |
0 ms |
340 KB |
Output is correct |
58 |
Correct |
1 ms |
332 KB |
Output is correct |
59 |
Correct |
0 ms |
332 KB |
Output is correct |
60 |
Correct |
1 ms |
332 KB |
Output is correct |
61 |
Correct |
1 ms |
332 KB |
Output is correct |
62 |
Correct |
1 ms |
332 KB |
Output is correct |
63 |
Correct |
0 ms |
332 KB |
Output is correct |
64 |
Correct |
1 ms |
332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
0 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 |
0 ms |
332 KB |
Output is correct |
8 |
Correct |
0 ms |
332 KB |
Output is correct |
9 |
Correct |
0 ms |
332 KB |
Output is correct |
10 |
Correct |
0 ms |
332 KB |
Output is correct |
11 |
Correct |
10 ms |
448 KB |
Output is correct |
12 |
Correct |
3 ms |
332 KB |
Output is correct |
13 |
Correct |
5 ms |
332 KB |
Output is correct |
14 |
Correct |
6 ms |
332 KB |
Output is correct |
15 |
Correct |
6 ms |
420 KB |
Output is correct |
16 |
Correct |
10 ms |
452 KB |
Output is correct |
17 |
Correct |
11 ms |
460 KB |
Output is correct |
18 |
Correct |
10 ms |
448 KB |
Output is correct |
19 |
Correct |
10 ms |
456 KB |
Output is correct |
20 |
Correct |
10 ms |
460 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
332 KB |
Output is correct |
8 |
Correct |
0 ms |
332 KB |
Output is correct |
9 |
Correct |
0 ms |
332 KB |
Output is correct |
10 |
Correct |
0 ms |
340 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 |
332 KB |
Output is correct |
14 |
Correct |
1 ms |
332 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
0 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
336 KB |
Output is correct |
20 |
Correct |
1 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
340 KB |
Output is correct |
22 |
Correct |
0 ms |
340 KB |
Output is correct |
23 |
Correct |
1 ms |
332 KB |
Output is correct |
24 |
Correct |
1 ms |
332 KB |
Output is correct |
25 |
Correct |
0 ms |
332 KB |
Output is correct |
26 |
Correct |
1 ms |
340 KB |
Output is correct |
27 |
Correct |
1 ms |
332 KB |
Output is correct |
28 |
Correct |
1 ms |
332 KB |
Output is correct |
29 |
Correct |
1 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
31 |
Correct |
0 ms |
332 KB |
Output is correct |
32 |
Correct |
0 ms |
332 KB |
Output is correct |
33 |
Correct |
0 ms |
332 KB |
Output is correct |
34 |
Correct |
1 ms |
340 KB |
Output is correct |
35 |
Correct |
1 ms |
332 KB |
Output is correct |
36 |
Correct |
1 ms |
332 KB |
Output is correct |
37 |
Correct |
0 ms |
332 KB |
Output is correct |
38 |
Correct |
0 ms |
332 KB |
Output is correct |
39 |
Correct |
1 ms |
340 KB |
Output is correct |
40 |
Correct |
1 ms |
332 KB |
Output is correct |
41 |
Correct |
0 ms |
332 KB |
Output is correct |
42 |
Correct |
0 ms |
332 KB |
Output is correct |
43 |
Correct |
0 ms |
332 KB |
Output is correct |
44 |
Correct |
0 ms |
332 KB |
Output is correct |
45 |
Correct |
1 ms |
332 KB |
Output is correct |
46 |
Correct |
1 ms |
340 KB |
Output is correct |
47 |
Correct |
1 ms |
332 KB |
Output is correct |
48 |
Correct |
1 ms |
332 KB |
Output is correct |
49 |
Correct |
0 ms |
332 KB |
Output is correct |
50 |
Correct |
1 ms |
340 KB |
Output is correct |
51 |
Correct |
0 ms |
332 KB |
Output is correct |
52 |
Correct |
0 ms |
332 KB |
Output is correct |
53 |
Correct |
0 ms |
340 KB |
Output is correct |
54 |
Correct |
0 ms |
332 KB |
Output is correct |
55 |
Correct |
1 ms |
332 KB |
Output is correct |
56 |
Correct |
1 ms |
332 KB |
Output is correct |
57 |
Correct |
0 ms |
340 KB |
Output is correct |
58 |
Correct |
1 ms |
332 KB |
Output is correct |
59 |
Correct |
0 ms |
332 KB |
Output is correct |
60 |
Correct |
1 ms |
332 KB |
Output is correct |
61 |
Correct |
1 ms |
332 KB |
Output is correct |
62 |
Correct |
1 ms |
332 KB |
Output is correct |
63 |
Correct |
0 ms |
332 KB |
Output is correct |
64 |
Correct |
1 ms |
332 KB |
Output is correct |
65 |
Correct |
1 ms |
336 KB |
Output is correct |
66 |
Correct |
1 ms |
332 KB |
Output is correct |
67 |
Correct |
1 ms |
336 KB |
Output is correct |
68 |
Correct |
1 ms |
332 KB |
Output is correct |
69 |
Correct |
0 ms |
332 KB |
Output is correct |
70 |
Correct |
1 ms |
332 KB |
Output is correct |
71 |
Correct |
0 ms |
332 KB |
Output is correct |
72 |
Correct |
1 ms |
332 KB |
Output is correct |
73 |
Correct |
1 ms |
332 KB |
Output is correct |
74 |
Correct |
1 ms |
332 KB |
Output is correct |
75 |
Correct |
0 ms |
332 KB |
Output is correct |
76 |
Correct |
1 ms |
332 KB |
Output is correct |
77 |
Correct |
1 ms |
332 KB |
Output is correct |
78 |
Correct |
1 ms |
332 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 |
348 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 |
340 KB |
Output is correct |
87 |
Correct |
1 ms |
332 KB |
Output is correct |
88 |
Correct |
1 ms |
332 KB |
Output is correct |
89 |
Correct |
14 ms |
416 KB |
Output is correct |
90 |
Correct |
10 ms |
408 KB |
Output is correct |
91 |
Correct |
10 ms |
332 KB |
Output is correct |
92 |
Correct |
9 ms |
332 KB |
Output is correct |
93 |
Correct |
12 ms |
332 KB |
Output is correct |
94 |
Correct |
9 ms |
348 KB |
Output is correct |
95 |
Correct |
14 ms |
424 KB |
Output is correct |
96 |
Correct |
14 ms |
460 KB |
Output is correct |
97 |
Correct |
11 ms |
332 KB |
Output is correct |
98 |
Correct |
14 ms |
332 KB |
Output is correct |
99 |
Correct |
10 ms |
412 KB |
Output is correct |
100 |
Correct |
10 ms |
412 KB |
Output is correct |
101 |
Correct |
10 ms |
332 KB |
Output is correct |
102 |
Correct |
10 ms |
332 KB |
Output is correct |
103 |
Correct |
10 ms |
332 KB |
Output is correct |
104 |
Correct |
8 ms |
332 KB |
Output is correct |
105 |
Correct |
10 ms |
332 KB |
Output is correct |
106 |
Correct |
13 ms |
420 KB |
Output is correct |
107 |
Correct |
11 ms |
332 KB |
Output is correct |
108 |
Correct |
13 ms |
332 KB |
Output is correct |
109 |
Correct |
10 ms |
332 KB |
Output is correct |
110 |
Correct |
10 ms |
344 KB |
Output is correct |
111 |
Correct |
9 ms |
332 KB |
Output is correct |
112 |
Correct |
10 ms |
332 KB |
Output is correct |
113 |
Correct |
17 ms |
332 KB |
Output is correct |
114 |
Correct |
14 ms |
416 KB |
Output is correct |
115 |
Correct |
9 ms |
336 KB |
Output is correct |
116 |
Correct |
11 ms |
332 KB |
Output is correct |
117 |
Correct |
14 ms |
332 KB |
Output is correct |
118 |
Correct |
13 ms |
340 KB |
Output is correct |
119 |
Correct |
13 ms |
408 KB |
Output is correct |
120 |
Correct |
13 ms |
332 KB |
Output is correct |
121 |
Correct |
14 ms |
416 KB |
Output is correct |
122 |
Correct |
10 ms |
332 KB |
Output is correct |
123 |
Correct |
9 ms |
404 KB |
Output is correct |
124 |
Correct |
13 ms |
332 KB |
Output is correct |
125 |
Correct |
7 ms |
332 KB |
Output is correct |
126 |
Correct |
10 ms |
332 KB |
Output is correct |
127 |
Correct |
9 ms |
332 KB |
Output is correct |
128 |
Correct |
14 ms |
416 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 |
344 KB |
Output is correct |
132 |
Correct |
1 ms |
332 KB |
Output is correct |
133 |
Correct |
1 ms |
332 KB |
Output is correct |
134 |
Correct |
1 ms |
332 KB |
Output is correct |
135 |
Correct |
1 ms |
348 KB |
Output is correct |
136 |
Correct |
0 ms |
360 KB |
Output is correct |
137 |
Correct |
1 ms |
340 KB |
Output is correct |
138 |
Correct |
1 ms |
332 KB |
Output is correct |
139 |
Correct |
1 ms |
352 KB |
Output is correct |
140 |
Correct |
1 ms |
348 KB |
Output is correct |
141 |
Correct |
1 ms |
332 KB |
Output is correct |
142 |
Correct |
0 ms |
332 KB |
Output is correct |
143 |
Correct |
1 ms |
332 KB |
Output is correct |
144 |
Correct |
11 ms |
460 KB |
Output is correct |
145 |
Correct |
11 ms |
452 KB |
Output is correct |