Submission #1172811

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172811		Tsagana	Bitaro’s Party (JOI18_bitaro)	C++20	7 / 100	848 ms	531944 KiB

bitaro

#include<bits/stdc++.h>

#define IOS ios_base::sync_with_stdio(false);cin.tie();cout.tie();
#define all(x) x.begin(), x.end()
#define int long long
#define pq priority_queue
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define pb push_back
#define pp pop_back
#define F first
#define S second

using namespace std;

vector<pair<int, int>> dp[100010];
vector<int> adj[100010]; 
bool nah[100010];

void merge(int t, int s){
	auto cs = dp[s];
	for (auto &i: cs) i.F++;
	
	vector<pair<int, int>> v;
	int l = 0, r = 0;
	while (l < dp[t].size() && r < cs.size()) {
		if (dp[t][l] > cs[r]) v.pb(dp[t][l++]);
		else v.pb(cs[r++]);
	}
	while (l < dp[t].size()) v.pb(dp[t][l++]);
	while (r < cs.size()) v.pb(cs[r++]);

	dp[t].clear();
	for (auto &i : v) {
		if(!nah[i.S]) dp[t].pb(i);
		nah[i.S] = 1;
	}

	for (auto &i: dp[t]) nah[i.S] = 0;

	if (dp[t].size() > 318) dp[t].resize(318);
}

int sol1(int i) {
	for(auto &i: dp[i]) if (!nah[i.S]) return i.F;
	return -1;
}

int sol2(int t){
	vector<int> dp(100010, -1e9);
	for(int j = 1; j <= t; j++) {
		if (!nah[j]) dp[j] = 0;
		for (auto &i: adj[j]) dp[j] = max(dp[j], dp[i] + 1);
	}
	return dp[t] < 0 ? -1 : dp[t];
}

void solve () {
	int n, m, q;
	cin >> n >> m >> q;
	for (int i = 0; i < m; i++) {
		int a, b;
		cin >> a >> b;
		adj[b].pb(a);
	}
	for (int i = 1; i <= n; i++) {
		dp[i] = {{0, i}};
		for (auto j: adj[i]) merge(i, j);
	}

	while (q--) {
		int t, a;
		cin >> t >> a;

		vector<int> c;
		for (int i = 0; i < a; i++) {
			int b; cin >> b;
			nah[b] = 1;
			c.pb(b);
		}

		if (a <= 318) cout << sol1(t) << '\n';
		else cout << sol2(t) << '\n';

		for (auto &i: c) nah[i] = 0;
	}
}
signed main() {IOS solve(); return 0;}

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