Submission #1102035

#	Time	Username	Problem	Language	Result	Execution time	Memory
1102035		crafticat	Village (BOI20_village)	C++17	6 / 100	26 ms	508 KiB

Village

#include "bits/stdc++.h"

using namespace std;
using ll = long long;
template<typename T>
using V = vector<T>;
using vi = V<ll>;
using vvi = V<vi>;
using pi = pair<ll,ll>;
using vpi = V<pi>;

#define F0R(i, n) for(ll i = 0; i < n;i++)
#define FOR(i,a, n) for(ll i = a; i < n;i++)
#define pb push_back

vvi g;
vi to;
vi dist;

void calc(ll x, ll p, ll d = 0) {
    dist[x] = d;
    for (auto y : g[x]) {
        if (y == p) continue;
        calc(y,x, d + 1);
    }
}

int solve(int start, ll n) {
    ll root = start;
    ll sum = 0;
    V<bool> vis(n + 1);

    while (true) {
        calc(root, -1, 0);
        ll sel = -1;

        FOR(i,1,n + 1) {
            if (vis[i]) continue;
            if (sel == -1 || dist[i] >= dist[sel]) sel = i;
        }

        if (sel == -1) break;
        to[root] = sel;
        vis[root] = true;
        root = sel;
        sum += dist[sel];
    }

    calc(root, -1, 0);
    to[root] = start;
    sum += dist[start];
    return sum;
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);

    ll n; cin >> n;
    g.resize(n + 1);
    to.resize(n + 1);
    dist.resize(n + 1);

    F0R(i, n - 1) {
        ll a, b; cin >> a >> b;
        g[a].pb(b);
        g[b].pb(a);
    }

    ll bestRoot = 1, bestSum = 0;
    FOR(i,1, min((int)n + 1, 4)) {
        int y = solve(i, n);
        if (y > bestSum) {
            bestSum = y;
            bestRoot = i;
        }

    }
    int sum = solve(bestRoot,n);

    cout << sum << " " << sum << "\n";
    FOR(i, 1, n + 1) {
        cout << to[i] << " ";
    }
    cout << "\n";
    FOR(i, 1, n + 1) {
        cout << to[i] << " ";
    }

    return 0;
}

• Subtask 1: 6 / 12
• Subtask 2: 0 / 38
• Subtask 3: 0 / 50