Submission #158189

#	Time	Username	Problem	Language	Result	Execution time	Memory
158189		fedoseevtimofey	Bitaro’s Party (JOI18_bitaro)	C++14	100 / 100	1597 ms	224956 KiB

bitaro

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

const int N = 1e5 + 7;
const int Inf = 1e9;

vector <int> g[N];
vector <int> rg[N];
bool used[N];
int dp[N];
int ban[N];
bool have[N];

vector <pair <int, int>> best[N];

vector <int> ts;

void dfs(int u) {
    used[u] = 1;
    for (int v : g[u]) {
        if (!used[v]) {
            dfs(v);
        }
    }
    ts.push_back(u);
}

const int K = 200;

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0); cout.setf(ios::fixed); cout.precision(20);
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif
    int n, m, q;
    cin >> n >> m >> q;
    for (int i = 0; i < m; ++i) {
        int u, v;
        cin >> u >> v;
        --u, --v;
        g[u].push_back(v);
        rg[v].push_back(u);
    }
    for (int i = 0; i < n; ++i) {
        if (!used[i]) {
            dfs(i);
        }
    }

    for (int i = (int)ts.size() - 1; i >= 0; --i) { 
        int u = ts[i];
        int sz = rg[u].size();
        vector <int> uk(sz);
        while (true) {
            pair <int, int> mx = {0, u};
            int id = -1;
            for (int i = 0; i < sz; ++i) {
                while (uk[i] < (int)best[rg[u][i]].size() && have[best[rg[u][i]][uk[i]].second]) {
                    ++uk[i];
                }   
                if (uk[i] < (int)best[rg[u][i]].size()) {
                    auto cp = best[rg[u][i]][uk[i]];
                    ++cp.first;
                    if (cp > mx) {
                        mx = cp;
                        id = i;
                    }
                }
            }
            if (id == -1) {
                best[u].push_back(mx);
                break;
            } else {
                best[u].push_back(mx);
                ++uk[id];
                have[mx.second] = 1;
                if ((int)best[u].size() == K) break;
            }
        }
        for (int v : rg[u]) {
            for (auto p : best[v]) {
                have[p.second] = 0;
            }
        }
    }

    while (q--) {
        int t;
        cin >> t;
        --t;   
        int y;
        cin >> y;
        vector <int> who;
        for (int i = 0; i < y; ++i) {
            int x;
            cin >> x;
            --x;
            who.push_back(x);
            ban[x] = 1;
        }
        if (y >= K) {
            fill(dp, dp + n, -Inf);
            dp[t] = 0;
            for (int x : ts) {
                for (int v : g[x]) {
                    dp[x] = max(dp[x], dp[v] + 1);
                }
            }
            int ans = -1;
            for (int i = 0; i < n; ++i) if (!ban[i]) ans = max(ans, dp[i]);
            cout << ans << '\n';
        } else {
            int ans = -1;
            for (auto p : best[t]) {
                if (!ban[p.second]) {
                    ans = max(ans, p.first);
                }
            }
            cout << ans << '\n';
        }
        for (int x : who) ban[x] = 0;
    }
}

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