Submission #947030

#	Time	Username	Problem	Language	Result	Execution time	Memory
947030		alextodoran	Security Guard (JOI23_guard)	C++17	100 / 100	728 ms	81084 KiB

guard

/**
 _  _   __  _ _ _  _  _ _
 |a  ||t  ||o    d | |o  |
| __    _| | _ | __|  _ |
| __ |/_  | __  /__\ / _\|

**/

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N_MAX = 200000;
const int M_MAX = 400000;

int N, M, Q;
int S[N_MAX + 2];
int edge_u[M_MAX + 2], edge_v[M_MAX + 2];

int order[M_MAX + 2];

int leader[N_MAX + 2];
int find_leader (int u) {
    return (leader[u] == 0 ? u : leader[u] = find_leader(leader[u]));
}
bool join (int u, int v) {
    u = find_leader(u);
    v = find_leader(v);
    if (u != v) {
        leader[u] = v;
        return true;
    }
    return false;
}

vector <int> adj[N_MAX + 2];

int root;
ll cost;

void init () {
    int mx = 0;
    for (int u = 1; u <= N; u++) {
        cost -= S[u];
        mx = max(mx, S[u]);
    }
    cost += mx;
    root = 1;
    for (int u = 2; u <= N; u++) {
        if (S[u] < S[root]) {
            root = u;
        }
    }
    for (int u = 1; u <= N; u++) {
        if (u != root) {
            cost += S[u] + S[root];
        }
    }
}

ll answer[N_MAX + 2];

struct Edge {
    int u, v;
    int delta;
};
bool operator < (const Edge &e1, const Edge &e2) {
    return make_tuple(e1.delta, e1.u, e1.v) < make_tuple(e2.delta, e2.u, e2.v);
}
Edge operator - (const Edge &e, const int &val) {
    return Edge{e.u, e.v, e.delta - val};
}

int min_comp[N_MAX + 2];
set <Edge> edges[N_MAX + 2];
set <Edge> best_edges;

signed main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> N >> M >> Q;
    for (int u = 1; u <= N; u++) {
        cin >> S[u];
    }
    for (int i = 1; i <= M; i++) {
        cin >> edge_u[i] >> edge_v[i];
    }
    iota(order + 1, order + M + 1, 1);
    sort(order + 1, order + M + 1, [&] (const int &i, const int &j) {
        return S[edge_u[i]] + S[edge_v[i]] < S[edge_u[j]] + S[edge_v[j]];
    });
    for (int _ = 1; _ <= M; _++) {
        int i = order[_];
        if (join(edge_u[i], edge_v[i]) == true) {
            adj[edge_u[i]].push_back(edge_v[i]);
            adj[edge_v[i]].push_back(edge_u[i]);
        }
    }
    init();
    for (int i = N - 1; i <= Q; i++) {
        answer[i] = cost;
    }
    fill(leader + 1, leader + N + 1, 0);
    for (int u = 1; u <= N; u++) {
        min_comp[u] = S[u];
        for (int v : adj[u]) {
            edges[u].insert(Edge{u, v, S[u] + S[v]});
        }
        best_edges.insert(*edges[u].begin() - S[u]);
    }
    for (int k = N - 2; k >= 0; k--) {
        Edge e = *best_edges.begin();
        int u = e.u, v = e.v, delta = e.delta;
        int U = find_leader(u), V = find_leader(v);
        best_edges.erase(*edges[U].begin() - min_comp[U]);
        best_edges.erase(*edges[V].begin() - min_comp[V]);
        edges[U].erase(Edge{u, v, S[u] + S[v]});
        edges[V].erase(Edge{v, u, S[v] + S[u]});
        cost += delta;
        cost -= S[root];
        answer[k] = cost;
        if ((int) edges[U].size() > (int) edges[V].size()) {
            swap(U, V);
        }
        for (Edge e : edges[U]) {
            edges[V].insert(e);
        }
        edges[U].clear();
        min_comp[V] = min(min_comp[U], min_comp[V]);
        leader[U] = V;
        best_edges.insert(*edges[V].begin() - min_comp[V]);
    }
    for (int i = 0; i <= Q; i++) {
        cout << answer[i] << "\n";
    }

    return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 13 / 13
• Subtask 5: 8 / 8
• Subtask 6: 18 / 18
• Subtask 7: 24 / 24