Submission #670107

#	Time	Username	Problem	Language	Result	Execution time	Memory
670107		SanguineChameleon	Bitaro’s Party (JOI18_bitaro)	C++14	100 / 100	1992 ms	425780 KiB

bitaro

// BEGIN BOILERPLATE CODE

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

#ifdef KAMIRULEZ
	const bool kami_loc = true;
	const long long kami_seed = 69420;
#else
	const bool kami_loc = false;
	const long long kami_seed = chrono::steady_clock::now().time_since_epoch().count();
#endif

const string kami_fi = "kamirulez.inp";
const string kami_fo = "kamirulez.out";
mt19937_64 kami_gen(kami_seed);

long long rand_range(long long rmin, long long rmax) {
	uniform_int_distribution<long long> rdist(rmin, rmax);
	return rdist(kami_gen);
}

long double rand_real(long double rmin, long double rmax) {
	uniform_real_distribution<long double> rdist(rmin, rmax);
	return rdist(kami_gen);
}

void file_io(string fi, string fo) {
	if (fi != "" && (!kami_loc || fi == kami_fi)) {
		freopen(fi.c_str(), "r", stdin);
	}
	if (fo != "" && (!kami_loc || fo == kami_fo)) {
		freopen(fo.c_str(), "w", stdout);
	}
}

void set_up() {
	if (kami_loc) {
		file_io(kami_fi, kami_fo);
	}
	ios_base::sync_with_stdio(0);
	cin.tie(0);
}

void just_do_it();

void just_exec_it() {
	if (kami_loc) {
		auto pstart = chrono::steady_clock::now();
		just_do_it();
		auto pend = chrono::steady_clock::now();
		long long ptime = chrono::duration_cast<chrono::milliseconds>(pend - pstart).count();
		string bar(50, '=');
		cout << '\n' << bar << '\n';
		cout << "Time: " << ptime << " ms" << '\n';
	}
	else {
		just_do_it();
	}
}

int main() {
	set_up();
	just_exec_it();
	return 0;
}

// END BOILERPLATE CODE

// BEGIN MAIN CODE

const int ms = 1e5 + 20;
const int bl = 3e2 + 20;
vector<int> adj1[ms];
vector<int> adj2[ms];
vector<pair<int, int>> d[ms];
int a[ms];
bool f[ms];
int dp[ms];

int solve(int u) {
	if (dp[u] != -2) {
		return dp[u];
	}
	dp[u] = (f[u] ? -1 : 0);
	for (auto v: adj2[u]) {
		if (solve(v) != -1) {
			dp[u] = max(dp[u], solve(v) + 1);
		}
	}
	return dp[u];
}

void just_do_it() {
	int n, m, q;
	cin >> n >> m >> q;
	for (int i = 1; i <= n; i++) {
		d[i] = {{0, i}};
	}
	for (int i = 0; i < m; i++) {
		int u, v;
		cin >> u >> v;
		adj1[u].push_back(v);
		adj2[v].push_back(u);
	}
	for (int u = 1; u <= n; u++) {
		for (auto v: adj1[u]) {
			vector<pair<int, int>> uz(d[u].begin(), d[u].end());
			for (auto &x: uz) {
				x.first++;
			}
			vector<pair<int, int>> tmp(d[u].size() + d[v].size());
			merge(uz.begin(), uz.end(), d[v].begin(), d[v].end(), tmp.begin(), greater<pair<int, int>>());
			d[v].clear();
			for (auto x: tmp) {
				if (!f[x.second]) {
					d[v].push_back(x);
				}
				f[x.second] = true;
			}
			for (auto x: tmp) {
				f[x.second] = false;
			}
			if (d[v].size() > bl) {
				d[v].resize(bl);
			}
		}
	}
	for (int i = 0; i < q; i++) {
		int u;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0; j < k; j++) {
			cin >> a[j];
			f[a[j]] = true;
		}
		if (k < bl) {
			int res = -1;
			for (auto x: d[u]) {
				if (!f[x.second]) {
					res = x.first;
					break;
				}
			}
			cout << res << '\n';
		}
		else {
			for (int j = 1; j <= n; j++) {
				dp[j] = -2;
			}
			cout << solve(u) << '\n';
		}
		for (int j = 0; j < k; j++) {
			f[a[j]] = false;
		}
	}
}

// END MAIN CODE

Compilation message (stderr)

bitaro.cpp: In function 'void file_io(std::string, std::string)':
bitaro.cpp:30:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |   freopen(fi.c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:33:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |   freopen(fo.c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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