Submission #1127648

#	Time	Username	Problem	Language	Result	Execution time	Memory
1127648		moonpay	Bitaro’s Party (JOI18_bitaro)	C++20	14 / 100	650 ms	253388 KiB

bitaro

#include <algorithm>
#include <cassert>
#include <iostream>
#include <vector>
#include <set>

using namespace std;
using ll = long long;
using vl = vector<ll>;

istream &operator>>(istream &os, vl &a) {
    for (auto &x: a) cin >> x;
    return os;
}

constexpr int N = 200200;
constexpr int B = 100;
vector<int> g[N], ig[N];

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m, q;
    cin >> n >> m >> q;
    for (int i = 0; i < m; i++) {
        int s, e;
        cin >> s >> e;
        g[s].push_back(e);
        ig[e].push_back(s);
    }
    std::vector<std::vector<pair<int, int> > > least(n + 1, std::vector<pair<int, int> >());
    std::vector<int> used(n + 1, -1);
    least[1] = {{0, 1}};
    for (int i = 2; i <= n; i++) {
        vector<int> have;
        for (auto &d: ig[i]) {
            for (auto &[x, y]: least[d]) {
                used[y] = max(used[y], x + 1);
                have.push_back(y);
            }
        }
        least[i].emplace_back(0, i);
        for (auto &x: have) {
            least[i].emplace_back(used[x], x);
        }
        sort(least[i].begin(), least[i].end());
        reverse(least[i].begin(), least[i].end());
        while (least[i].size() > B) {
            least[i].pop_back();
        }
        for (auto &d: have) used[d] = -1;
    }
    for (int i = 0; i < q; i++) {
        int t, y;
        cin >> t >> y;
        vector<int> blocked(y);
        std::set<int> bl;
        for (int j = 0; j < y; j++) {
            cin >> blocked[j];
            bl.insert(blocked[j]);
        }
        if (y >= B) {
            std::vector<int> dp(n + 1, -1);
            dp[t] = 0;
            for (int j = t; j >= 1; j--) {
                if (dp[j] == -1) continue;
                for (const auto &d: ig[j]) {
                    dp[d] = max(dp[d], dp[j] + 1);
                }
            }
            int value = -1;
            for (int g = 1; g <= t; g++) {
                if (!bl.contains(g)) value = max(value, dp[g]);
            }
            std::cout << value << "\n";
        } else {
            int value = -1;
            for (const auto &d: least[t]) {
                if (!bl.contains(d.second)) value = max(value, d.first);
            }
            std::cout << value << "\n";
        }
    }
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 0 / 86