Submission #707339

#	Time	Username	Problem	Language	Result	Execution time	Memory
707339		Stickfish	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	36 / 100	1033 ms	6968 KiB

skyscraper

#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
#include <bitset>
using namespace std;

const int MAXN = 30100;
const int SQN = 200;
const int INF = 1e9 + 177013;
pair<int, int> dogs[MAXN];
vector<int> jlen[MAXN];

struct modmin {
    void resize(int n) {
        sz = n;
        used.resize(sz);
        pivots = {{-INF, 10}, {INF, 10}};
    }

    void insert_pivot(int x, int vl) {
        pivots.insert(lower_bound(pivots.begin(), pivots.end(), pair<int, int>{x, -1}), {x, vl});
    }

    void deactivate(int x) {
        used[x] = 1;
    }

    pair<int, int> get_min() {
        int i = 0;
        pair<int, int> ans = {INF, INF};
        for (int x = 0; x < sz; ++x) {
            if (pivots[i].first == INF)
                break;
            if (x - pivots[i].first + pivots[i].second > pivots[i + 1].first - x + pivots[i + 1].second)
                ++i;
            if (!used[x])
                ans = min(ans, {abs(x - pivots[i].first) + pivots[i].second, x});
        }
        return ans;
    }
 //private:
     int sz;
     vector<pair<int, int>> pivots;
     vector<bool> used;
};

bitset<MAXN> used;
int dist_long[MAXN];
modmin dist_short[SQN][SQN];

signed main() {
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < m; ++i) {
        cin >> dogs[i].first >> dogs[i].second;
        jlen[dogs[i].first].push_back(dogs[i].second);
    }
    int s = dogs[0].first;
    int t = dogs[1].first;
    for (int i = 0; i < n; ++i)
        dist_long[i] = INF;
    dist_long[s] = 0;
    for (int d = 1; d < SQN; ++d) {
        for (int md = 0; md < n && md < d; ++md) {
            dist_short[d][md].resize((n - md - 1) / d + 1);
        }
    }
    set<pair<int, int>> rdist_short;
    int T = n;
    while (T--) {
        //cout << "A" << endl;
        pair<int, int> opt = {INF, INF};
        for (int i = 0; i < n; ++i) {
            if (!used[i])
                opt = min(opt, {dist_long[i], i});
        }
        if (rdist_short.size()) {
            opt = min(opt, *rdist_short.begin());
        }
        auto [dist, v] = opt;
        if (dist >= INF)
            break;
        dist_long[v] = dist;
        used[v] = 1;
        for (int d = 1; d < SQN; ++d) {
            int md = v % d;
            pair<int, int> cval = dist_short[d][md].get_min();
            cval.second = md + d * cval.second;
            rdist_short.erase(cval);

            dist_short[d][md].deactivate(v / d);

            pair<int, int> ncval = dist_short[d][md].get_min();
            ncval.second = md + d * ncval.second;
            rdist_short.insert(ncval);
        }
        for (auto p : jlen[v]) {
            if (p >= SQN) {
                for (int k = 1; p * k <= v; ++k)
                    dist_long[v - p * k] = min(dist_long[v - p * k], dist + k);
                for (int k = 1; v + p * k < n; ++k)
                    dist_long[v + p * k] = min(dist_long[v + p * k], dist + k);
            } else {
                int md = v % p;
                //cout << "! " << p << ' ' << md << endl;
                pair<int, int> cval = dist_short[p][md].get_min();
                cval.second = md + p * cval.second;
                rdist_short.erase(cval);

                dist_short[p][md].insert_pivot(v / p, dist);

                pair<int, int> ncval = dist_short[p][md].get_min();
                ncval.second = md + p * ncval.second;
                rdist_short.insert(ncval);
            }
        }
    }
    if (dist_long[t] >= INF)
        cout << "-1\n";
    else
        cout << dist_long[t] << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43