Submission #204108

#	Time	Username	Problem	Language	Result	Execution time	Memory
204108		extraterrestrial	Bitaro’s Party (JOI18_bitaro)	C++14	100 / 100	1341 ms	115156 KiB

bitaro

#include <bits/stdc++.h>
typedef long long ll;
typedef long double ld;
using namespace std;
#define F first
#define S second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define SZ(x) (int)(x).size()
//#define int ll

const int N = 1e5 + 10;
const int B = 100;
const int INF = 1e9 + 10;
vector<pair<int, int>> best[N];
vector<int> g[N];
int used[N], timer, dp[N], ptr[N];
signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
	int n, m, q;
	cin >> n >> m >> q;
	for (int i = 0; i < m; i++) {
		int u, v;
		cin >> u >> v;
		g[v].pb(u);
	}
	for (int i = 1; i <= n; i++) {
		timer++;
		set<pair<int, int>> st;
		for (int v : g[i]) {
			ptr[v] = 0;
			st.insert({-best[v][0].F, v});
		}
		while (!st.empty() && SZ(best[i]) < B) {
			int v = st.begin()->S;
			st.erase(st.begin());
			if (used[best[v][ptr[v]].S] < timer) {
				used[best[v][ptr[v]].S] = timer;
				best[i].pb(make_pair(best[v][ptr[v]].F + 1, best[v][ptr[v]].S));
			}
			ptr[v]++;
			if (ptr[v] < SZ(best[v])) {
				st.insert(make_pair(-best[v][ptr[v]].F, v));
			}
		}
		if (SZ(best[i]) < B) {
			best[i].pb(make_pair(0, i));
		}
	}
	for (int i = 0; i < q; i++) {
		int v;
		cin >> v;
		int cnt;
		cin >> cnt;
		timer++;
		for (int j = 0; j < cnt; j++) {
			int x;
			cin >> x;
			used[x] = timer;
		}
		if (cnt < B) {
			int res = -1;
			for (auto it : best[v]) {
				if (used[it.S] < timer) {
					res = it.F;
					break;
				}
			}
			cout << res << '\n';
		}
		else {
			for (int i = 1; i <= v; i++) {
				if (used[i] == timer) {
					dp[i] = -INF;
				}
				else {
					dp[i] = 0;
				}
				for (int v : g[i]) {
					dp[i] = max(dp[i], dp[v] + 1);
				}
				//cout << dp[i] << ' ';
			}		
			//cout << '\n';
			cout << (dp[v] < 0 ? -1 : dp[v]) << '\n';
		}
	}
} 

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