#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ff first
#define ss second
#define all(a) a.begin(), a.end()
const int mod = 1e9 + 7;
const int N = 2e5;
int dp[N];
int n;
vector<int> g[N];
int ans;
void dfs(int v, int par){
for(int to : g[v]){
if(to != par) dfs(to, v);
}
int to = par;
if(par != v && dp[v] == -1 && dp[to] == -1){
dp[v] = to, dp[to] = v;
ans+= 2;
}
}
main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
for(int i = 0;i < N; i++) dp[i] = -1;
cin >> n;
for(int i = 0;i < n-1; i++){
int a, b; cin >> a >> b;
g[a].push_back(b);
g[b].push_back(a);
}
dfs(1, 1);
for(int i = 1;i <= n; i++){
if(dp[i] == -1 or dp[i] == i){
int to = g[i][0];
dp[i] = i;
swap(dp[to], dp[i]);
ans+= 2;
}
}
cout << ans << '\n';
for(int i = 1;i <= n; i++) cout << dp[i] << ' ';
return 0;
}
Compilation message
Village.cpp:27:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
27 | main(){
| ^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6492 KB |
Unexpected end of file - int32 expected |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6492 KB |
Unexpected end of file - int32 expected |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
6492 KB |
Unexpected end of file - int32 expected |
| 2 |
Halted |
0 ms |
0 KB |
- |
