Submission #916712

#	Time	Username	Problem	Language	Result	Execution time	Memory
916712		ParsaGolestani	Bitaro’s Party (JOI18_bitaro)	C++14	0 / 100	5 ms	8792 KiB

bitaro

#include <bits/stdc++.h>
using namespace std;

const int N = 100'000;
const int SQ = 316;
const int INF = 1'000'000'000;

int n, m, q, mark[N + 10], dis[N + 10];
pair<int, int> far[N + 10][SQ + 10];
vector<pair<int, int>> in[N + 10];
vector<int> out[N + 10];

void readInput() {
    cin >> n >> m >> q;
    for (int i = 1; i <= m; i++) {
        int u, v;
        cin >> u >> v;
        out[u].push_back(v);
        in[v].push_back({u, 0});
    }
}

void calcFar() {
    for (int i = 1; i <= n; i++) {
        fill(far[i] + 1, far[i] + SQ + 1, make_pair(-INF, 0));
        for (int j = 1; j <= SQ; j++) {
            pair<pair<int, int>, int> res = {{-INF, 0}, -1};
            for (int x = 0; x < in[i].size(); x++) {
                int v = in[i][x].first, ind = in[i][x].second;
                while (ind < SQ && mark[far[v][ind + 1].second]) {
                    in[i][x].second++;
                    ind++;
                }
                if (ind < SQ)
                    res = max(res, make_pair(far[v][ind + 1], x));
            }
            far[i][j] = res.first;
            far[i][j].first++;
            mark[far[i][j].second] = true;
            if (res.second != -1)
                in[i][res.second].second++;
            /*if (far[i][j].second)
                cout << i << ' ' << j << ": " << far[i][j].first << ' ' << far[i][j].second << '\n';*/
        }
        for (int j = 1; j <= SQ; j++)
            if (far[i][j].first < 0) {
                far[i][j] = {0, i};
                break;
            }
        for (int j = 1; j <= SQ; j++)
            mark[far[i][j].second] = false;
    }
}

void query() {
    int u, cnt;
    cin >> u >> cnt;
    vector<int> vec;
    for (int i = 1; i <= cnt; i++) {
        int v;
        cin >> v;
        vec.push_back(v);
        mark[v] = true;
    }
    if (cnt < SQ) {
        for (int i = 1; i <= SQ; i++)
            if (!mark[far[u][i].second]) {
                cout << (far[u][i].first < 0? -1: far[u][i].first) << '\n';
                break;
            }
    }
    else {
        fill(dis + 1, dis + u + 1, -INF);
        dis[u] = 0;
        int ans = (mark[u]? -1: 0);
        for (int i = u - 1; i >= 1; i--) {
            for (auto v: out[i])
                dis[i] = max(dis[i], dis[v] + 1);
            if (!mark[i])
                ans = max(ans, dis[i]);
        }
        cout << ans << '\n';
    }
    for (auto x: vec)
        mark[x] = false;
}

void solve() {
    while (q--)
        query();
    cout.flush();
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    readInput();
    calcFar();
    solve();
    return 0;
}

Compilation message (stderr)

bitaro.cpp: In function 'void calcFar()':
bitaro.cpp:28:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |             for (int x = 0; x < in[i].size(); x++) {
      |                             ~~^~~~~~~~~~~~~~

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