#include <bits/stdc++.h>
using namespace std;
#define int int64_t
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;cin>>n;
vector<set<int>> g(n);
vector<vector<int>> bck(n);
vector<int> dg(n,0);
for (int i=1;i<n;i++) {
int a,b;cin>>a>>b;a--;b--;
g[a].insert(b);
g[b].insert(a);
bck[a].push_back(b);
bck[b].push_back(a);
dg[a]++;dg[b]++;
}
queue<int> q;
vector<bool> vis(n, false);
for (int i=0;i<n;i++) {
if (dg[i]==1){
q.push(i);
vis[i]=true;
}
}
int ans=0;
vector<int> conf(n,0);
for (int i=0;i<n;i++) {
conf[i]=i;
}
vector<bool> swp(n, false);
while (!q.empty()) {
int t=q.front();q.pop();
// cout<<t<<"\n";
cout.flush();
if (g[t].size() == 0) {
if (!swp[conf[t]]) {
swap(conf[t], conf[bck[t][0]]);
swp[conf[t]]=true;
// cout<<conf[t]+1<<" "<<conf[bck[t][0]]+1<<" bb\n";
ans += 2;
}
continue;
}
int ne = *g[t].begin();
vis[ne]=true;
if (g[ne].find(t) != g[ne].end()) g[ne].erase(g[ne].find(t));
for (int x:g[ne]) {
if (g[x].find(ne) != g[x].end()) g[x].erase(g[x].find(ne));
dg[x]--;
if (dg[x]<=1 && !vis[x]) {
q.push(x);
vis[x]=true;
}
}
if (!swp[ne] && !swp[t]) {
dg[ne]--;
ans+=2;
swap(conf[ne], conf[t]);
swp[ne]=swp[t]=true;
// cout<<conf[ne]+1<<" "<<conf[t]+1<<"\n";
}
}
cout<<ans<<"\n";
for (int x:conf) {
cout<<x+1<<" ";
}
cout<<"\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Unexpected end of file - int32 expected |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
0 ms |
348 KB |
Unexpected end of file - int32 expected |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Unexpected end of file - int32 expected |
2 |
Halted |
0 ms |
0 KB |
- |