#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
#define pb push_back
#define mp make_pair
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define lb lower_bound
#define ub upper_bound
#define sz(v) int((v).size())
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define endl '\n'
void solve() {
int n;
cin >> n;
vector <int> graph[n];
for (int i = 0; i < n-1; i++) {
int a, b;
cin >> a >> b;
a--; b--;
graph[a].pb(b);
graph[b].pb(a);
}
int cost[2];
cost[0] = cost[1] = 0;
vector <int> subtree(n);
vector <vector <int>> rear(2, vector <int> (n, -1));
function <int(int, int)> find_smallest = [&](int v, int p) {
vector <int> children;
subtree[v] = 1;
for (auto to : graph[v]) {
if (to == p) continue;
if (find_smallest(to, v)) {
children.pb(to);
}
subtree[v] += subtree[to];
}
if (sz(children) == 0) {
if (v) return 1;
cost[0] += 2;
int x = graph[v][0];
rear[0][v] = rear[0][x];
rear[0][x] = v;
}
else if (sz(children)&1) {
cost[0] += int(sz(children)/2)*4+2;
rear[0][v] = children[0];
rear[0][children[0]] = v;
for (int i = 1; i < sz(children); i += 2) {
rear[0][children[i]] = children[i+1];
rear[0][children[i+1]] = children[i];
}
}
else {
cost[0] += sz(children)*2;
rear[0][v] = children[1];
rear[0][children[1]] = children[0];
rear[0][children[0]] = v;
for (int i = 2; i < sz(children); i += 2) {
rear[0][children[i]] = children[i+1];
rear[0][children[i+1]] = children[i];
}
}
return 0;
};
find_smallest(0, 0);
function <int(int, int)> find_centroid = [&](int v, int p) {
for (auto to : graph[v]) {
if (to == p) continue;
if (subtree[to]*2 > subtree[0]) {
return find_centroid(to, v);
}
}
return v;
};
function <void(int, int)> find_largest = [&](int v, int p) {
if (v) {
cost[1] += min(subtree[v], subtree[0]-subtree[v])*2;
}
for (auto to : graph[v]) {
if (to == p) continue;
find_largest(to, v);
}
};
int centroid = find_centroid(0, 0);
find_largest(0, 0);
vector <vector <int>> children(sz(graph[centroid]));
function <void(int, int, int)> find_children = [&](int v, int p, int i) {
children[i].pb(v);
for (auto to : graph[v]) {
if (to == p) continue;
find_children(to, v, i);
}
};
for (int i = 0; i < sz(graph[centroid]); i++) {
find_children(graph[centroid][i], centroid, i);
}
if (n&1) {
rear[1][centroid] = children[1].back();
rear[1][children[1].back()] = children[0].back();
rear[1][children[0].back()] = centroid;
children[0].pop_back();
children[1].pop_back();
}
else {
rear[1][centroid] = children[0].back();
rear[1][children[0].back()] = centroid;
children[0].pop_back();
}
int l = 0, r = 1;
while (1) {
while (l < sz(children) && sz(children[l]) == 0) l++;
while (r < sz(children) && sz(children[r]) == 0) r++;
if (r == l) r++;
while (r < sz(children) && sz(children[r]) == 0) r++;
if (l >= sz(children) || r >= sz(children)) {
break;
}
rear[1][children[l].back()] = children[r].back();
rear[1][children[r].back()] = children[l].back();
children[l].pop_back();
children[r].pop_back();
}
cout << cost[0] << ' ' << cost[1] << endl;
for (int i = 0; i < 2; i++) {
for (auto to : rear[i]) cout << to+1 << ' ';
cout << endl;
}
}
int main() {
do_not_disturb
int t = 1;
//~ cin >> t;
while (t--) {
solve();
}
return 0;
}
/*
7
4 2
5 7
3 4
6 3
1 3
4 5
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Integer parameter [name=vi] equals to 0, violates the range [1, 4] |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
212 KB |
Integer parameter [name=vi] equals to 0, violates the range [1, 256] |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Integer parameter [name=vi] equals to 0, violates the range [1, 4] |
| 2 |
Halted |
0 ms |
0 KB |
- |
