Submission #1102076

#	Time	Username	Problem	Language	Result	Execution time	Memory
1102076		crafticat	Village (BOI20_village)	C++17	0 / 100	1 ms	592 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;
vi sum;
V<bool> vis;
vi org;
ll n;
// Dist, Node
V<queue<pi>> pqs;

void calcOrg(int x, int p, int orgP) {
    org[x] = orgP;
    for (auto y : g[x]) {
        if (y == p) continue;
        calcOrg(y,x,orgP == -1 ? x : orgP);
    }
}

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);
    }
}

void sumDfs(int x, int p) {
    sum[x] = 1;
    for (auto y : g[x]) {
        if (y == p) continue;
        sumDfs(y,x);
        sum[x] += sum[y];
    }
}

int findCentroid(int x, int p) {
    for (auto v : g[x]) {
        if (v == p) continue;
        if (sum[v] * 2 > n)
            return findCentroid(v,x);
    }
    return x;
}

void genPQS(int x, int p) {
    queue<tuple<int,int,int>> nodes;

    nodes.emplace(x, 1, p);
    pqs[x].emplace(x, 1);

    while (!nodes.empty()) {
        auto [cur, dist, par] = nodes.front(); nodes.pop();

        for (auto y : g[cur]) {
            if (y == par) continue;
            nodes.emplace(y, dist + 1, cur);
            pqs[x].emplace(y, dist + 1);
        }
    }
}

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

    cin >> n;
    g.resize(n + 1);
    to.resize(n + 1);
    vis.resize(n + 1);
    dist.resize(n + 1);
    org.resize(n + 1);
    sum.resize(n + 1);
    pqs.resize(n + 1);

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

    FOR(i, 1, n + 1) sum[i]++;
    sumDfs(1,-1);
    int cen = findCentroid(1,-1);
    sumDfs(cen,-1);
    int root = cen;
    ll sumV = 0;
    int last = -1;

    for (auto x : g[cen]) {
        genPQS(x, cen);
    }

    while (true) {

        int meow = -1;
        for (auto x : g[cen]) {
            if (x == last) continue;
            if (meow == -1 || (sum[x] > sum[meow])) meow = x;
        }

        if (meow == -1) meow = last;
        last = meow;
        sum[last]--;

        if (pqs[meow].empty()) break;
        auto [sel, distToCen] = pqs[meow].front(); pqs[meow].pop();

        to[root] = sel;
        root = sel;
        sumV += distToCen * 2;
    }

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

    return 0;
}

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