Submission #383473

#	Time	Username	Problem	Language	Result	Execution time	Memory
383473		morato	Bitaro’s Party (JOI18_bitaro)	C++17	14 / 100	2092 ms	175844 KiB

bitaro

#include <bits/stdc++.h>

using namespace std;

const int MAXN = 1e5 + 5;
const int MAXS = 200;

vector<int> adj[MAXN], rev[MAXN];

vector<pair<int, int>> caras[MAXN];

int in[MAXN], bosta[MAXN], best[MAXN];

pair<int, int> revIn[MAXN];

bool mark[MAXN], blocked[MAXN], valid[MAXN];

void merge(vector<pair<int, int>>& a, vector<pair<int, int>> b) {
	vector<pair<int, int>> result;
	int tamA = (int) a.size();
	int tamB = (int) b.size();
	int i = 0, j = 0, cnt = 0;
	for (; i < tamA && j < tamB && cnt < MAXS + 1;) {
		if (mark[a[i].second]) {
			i++;
			continue;
		} 
		if (mark[b[j].second]) {
			j++;
			continue;
		} 
		if (a[i].first > b[j].first + 1) {
			mark[a[i].second] = true;
			result.push_back(a[i++]);
		} else {
			mark[b[j].second] = true;
			result.emplace_back(b[j].first + 1, b[j].second);
			j++;
		}
		cnt++;
	}
	for (; i < tamA && cnt < MAXS + 1; i++) {
		if (mark[a[i].second]) continue;
		cnt++;
		result.push_back(a[i]);
	}
	for (; j < tamB && i + j < MAXS + 1; j++) {
		if (mark[b[j].second]) continue;
		cnt++;
		result.emplace_back(b[j].first + 1, b[j].second);
	}
	for (i = 0; i < (int) result.size(); i++) {
		mark[result[i].second] = false;
	}
	a = result;
}

int main(){
	int n, m, q;
	scanf("%d %d %d", &n, &m, &q);
	for (int i = 0; i < m; i++) {
		int a, b;
		scanf("%d %d", &a, &b);
		adj[a].push_back(b);
		rev[b].push_back(a);
		in[b]++;
		revIn[a].first++;
	}
	for (int i = 1; i <= n; i++) {
		revIn[i].second = revIn[i].first;
	}
	vector<int> lista;
	for (int i = 1; i <= n; i++) {
		caras[i].push_back({0, i});
		if (!in[i]) lista.push_back(i);
	}
	for (int i = 0; i < (int) lista.size(); i++) {
		int cur = lista[i];
		for (int nxt : adj[cur]) {
			in[nxt]--;
			if (!in[nxt]) lista.push_back(nxt);
			merge(caras[nxt], caras[cur]);
		}
	}
	for (int i = 0; i < q; i++) {
		int t, y;
		scanf("%d %d", &t, &y);
		for (int j = 0; j < y; j++) {
			scanf("%d", &bosta[j]);
			blocked[bosta[j]] = true;
		}
		if (y > MAXS) {
			vector<int> llista;
			for (int j = 1; j <= n; j++) {
				best[j] = -1;
				revIn[j].first = revIn[j].second;
				if (!revIn[j].first) llista.push_back(j);
			}
			valid[t] = true;
			best[t] = 0;
			for (int j = 0; j < (int) llista.size(); j++) {
				int cur = llista[j];
				for (int nxt : rev[cur]) {
					revIn[nxt].first--;
					if (!revIn[nxt].first) llista.push_back(nxt);
					if (valid[cur]) {
						valid[nxt] = true;
						best[nxt] = max(best[nxt], best[cur] + 1);
					}
				}
			}
			int ans = -1;
			for (int j = 1; j <= t; j++) {
				valid[j] = false;
				if (!blocked[j]) ans = max(ans, best[j]);
			}
			printf("%d\n", ans);
		} else {
			int ans = -1;
			for (auto x : caras[t]) {
				if (!blocked[x.second]) {
					ans = x.first;
					break;
				}
			}
			printf("%d\n", ans);
		}
		for (int j = 0; j < y; j++) {
			blocked[bosta[j]] = false;
		}
	}
	// for (int i = 1; i <= n; i++) {
	// 	cout << i << " -> ";
	// 	for (auto x : caras[i]) {
	// 		cout << "(" << x.first << ", " << x.second << "), ";
	// 	}
	// 	cout << '\n';
	// }
	return 0; 
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:60:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   60 |  scanf("%d %d %d", &n, &m, &q);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:63:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   63 |   scanf("%d %d", &a, &b);
      |   ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:87:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   87 |   scanf("%d %d", &t, &y);
      |   ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:89:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   89 |    scanf("%d", &bosta[j]);
      |    ~~~~~^~~~~~~~~~~~~~~~~

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