Submission #881283

#	Time	Username	Problem	Language	Result	Execution time	Memory
881283		bobbilyking	Bitaro’s Party (JOI18_bitaro)	C++17	7 / 100	2045 ms	121028 KiB

bitaro

#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")

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

typedef int ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef vector<ll> vl;
#define FD(i, r, l) for(ll i = r; i > (l); --i)

#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = l; i < (r); ++i)

#define NN 100010
#define M 1000000007 // 998244353

vector<ll> adj[NN];
ll n;
vector<ll> topo;

bool bad[NN];
ll dpfast[NN];
constexpr ll SN = 200;

vector<pl> dp[NN]; // only keep up to sqrt(N) things in here

int main(){
//    freopen("a.in", "r", stdin);
//    freopen("a.out", "w", stdout);

    ios_base::sync_with_stdio(false); cin.tie(0);
    cout << fixed << setprecision(20);
    cin >> n; G(m) G(q)
    while (m--) {
        G(s) G(e) adj[e].push_back(s);
    } 

    {
        bool vis[NN] = {};
        vector<ll> temp;
        auto dfs = [&](auto&& self, ll i) -> void {
            if (vis[i]) return;
            vis[i] = 1;
            for (auto y: adj[i]) self(self, y);
            temp.push_back(i);
        };
        F(i, 1, n+1) if (!vis[i]) {
            temp.clear();
            dfs(dfs, i);
            topo.insert(topo.end(), temp.rbegin(), temp.rend());
        }
    }

    for (auto x: topo) {
        map<ll, ll> dists; 
        dists[x] = 0;
        for (auto y: adj[x]) {
            for (auto z: dp[y]) dists[z.V] = max(dists[z.V], z.K+1); 
        }
        for (const auto &[k, v]: dists) dp[x].emplace_back(v, k);
        sort(A(dp[x]), greater()); while (dp[x].size() > SN) dp[x].pop_back();
    }

    while (q--) {
        G(t) G(m)
        vector<ll> v(m);
        for (auto &x: v) {
            cin >> x;
            bad[x]=1;
        }

        if (m >= SN) {
          	memset(dpfast, 0, sizeof dpfast);
            for (auto x: v) dpfast[x] = -n;
            for (auto x: topo) {
                for (auto y: adj[x]) dpfast[x] = max(dpfast[x], 1 + dpfast[y]);
            }
            cout << (dpfast[t] < 0 ? -1: dpfast[t]) << '\n';
        } else {
            ll ans = -1;
            for (auto [dist, node]: dp[t]) if (!bad[node]) ans = max(ans, dist);
            cout << ans << '\n';
        }
        for (auto x: v) bad[x] = 0;
    }
    
}

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