Submission #414036

#	Time	Username	Problem	Language	Result	Execution time	Memory
414036		ritul_kr_singh	Village (BOI20_village)	C++17	38 / 100	8 ms	9932 KiB

Village

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define sp << ' ' <<
#define nl << '\n'

const int MAXN = 1e5;

int n, s[MAXN], c, ans[2][MAXN], ansMax = 0, ansMin = 0;
vector<int> g[MAXN], a[MAXN];

void find(int u){
	int mx = 0; s[u] = 1;
	for(int v : g[u]){
		if(s[v]) continue;
		find(v), s[u] += s[v];
		mx = max(mx, s[v]);
		ansMax += min(n - s[v], s[v]);
		if(ans[0][v] == v) swap(ans[0][u], ans[0][v]), ansMin += 2;
	}
	if(max(mx, n - s[u]) <= n/2) c = u;
}

void add(int u, int p, vector<int> &b){
	b.push_back(u);
	for(int v : g[u]) if(v != p) add(v, u, b);
}

signed main(){
	cin.tie(0)->sync_with_stdio(0);
	int x, y; cin >> n;
	for(int i=1; i<n; ++i){
		cin >> x >> y; --x, --y;
		g[x].push_back(y);
		g[y].push_back(x);
	}

	for(int i=0; i<2; ++i) iota(ans[i], ans[i]+n, 0LL);

	find(0);

	priority_queue<array<int, 2>> q;
	if((x = n & 1)) swap(ans[1][c], ans[1][!c]);
	for(int u : g[c]){
		add(u, c, a[u]);
		if(!x && (int)a[u].size() + 1 <= n/2) a[u].push_back(c), x = 1;
		q.push({(int)a[u].size(), u});
	}

	while(!q.empty()){
		assert(q.size() > 1);
		array<int, 2> u = q.top(); q.pop();
		array<int, 2> v = q.top(); q.pop();
		swap(ans[1][a[u[1]].back()], ans[1][a[v[1]].back()]);
		a[u[1]].pop_back(), a[v[1]].pop_back();
		if(--u[0]) q.push(u);
		if(--v[0]) q.push(v);
	}

	for(int i=0; i<n; ++i) if(ans[0][i] == i) swap(ans[0][i], ans[0][g[i][0]]), ansMin += 2;

	cout << ansMin sp 2 * ansMax nl;
	for(int i=0; i<2; ++i){
		for(int j=0; j<n; ++j) cout << ans[i][j] + 1 << ' ';
		cout nl;
	}
}

• Subtask 1: 0 / 12
• Subtask 2: 38 / 38
• Subtask 3: 0 / 50