Submission #887644

#	Time	Username	Problem	Language	Result	Execution time	Memory
887644		TAhmed33	Jail (JOI22_jail)	C++98	61 / 100	3308 ms	1048576 KiB

jail

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 120025;
vector <int> adj[MAXN];
vector <int> adj2[501];
int n, m;
int l[501], r[501], deg[501];
vector <int> dd[MAXN];
vector <int> ls[501];
bool dfs (int pos, int par, int c) {
	if (pos == r[c]) {
		dd[pos].push_back(c);
		ls[c].push_back(pos);
		return 1;
	}
	bool f = 0;
	for (auto i : adj[pos]) {
		if (i != par) {
			f |= dfs(i, pos, c);
		}
	}
	if (f) {
		dd[pos].push_back(c);
		ls[c].push_back(pos);
	}
	return f;
}
int main () {
	ios::sync_with_stdio(0); cin.tie(0);
	int t = 1; cin >> t;
	while (t--) {
		cin >> n;
		for (int i = 1; i <= n; i++) {
			adj[i].clear();
			dd[i].clear();
		}
		for (int i = 1; i < n; i++) {
			int a, b;
			cin >> a >> b;
			adj[a].push_back(b);
			adj[b].push_back(a);
		}
		cin >> m;
		for (int i = 1; i <= m; i++) {
			deg[i] = 0; adj2[i].clear(); ls[i].clear();
		}
		for (int i = 1; i <= m; i++) {
			cin >> l[i] >> r[i];
			dfs(l[i], -1, i);
		}
		for (int i = 1; i <= n; i++) sort(dd[i].begin(), dd[i].end());
		bool flag3 = 0;
		for (int i = 1; i <= m; i++) {
			set <int> y;
			for (auto j : dd[l[i]]) y.insert(j);
			bool u2 = 0;
			for (auto j : dd[r[i]]) u2 |= y.count(j) && j != i;
			flag3 |= u2;
			u2 = 0;
			for (auto j : dd[l[i]]) if (j != i) u2 |= binary_search(dd[l[j]].begin(), dd[l[j]].end(), i);
			for (auto j : dd[r[i]]) if (j != i) u2 |= binary_search(dd[r[j]].begin(), dd[r[j]].end(), i);
			flag3 |= u2;
		}
		if (flag3) {
			cout << "No\n";
			continue;	
		}
		for (int i = 1; i <= m; i++) sort(ls[i].begin(), ls[i].end());
		for (int i = 1; i <= m; i++) {
			for (int j = 1; j <= m; j++) {
				if (i == j) continue;
				bool flag = 0;
				flag |= binary_search(ls[i].begin(), ls[i].end(), l[j]);
				flag |= binary_search(ls[j].begin(), ls[j].end(), r[i]);
				if (flag) adj2[i].push_back(j);
			}
		}
		for (int i = 1; i <= m; i++) {
			for (auto j : adj2[i]) {
				deg[j]++;
			}
		}
		vector <int> d;
		queue <int> cur;
		for (int i = 1; i <= m; i++) {
			if (deg[i] == 0) {
				cur.push(i);
			}
		}
		while (!cur.empty()) {
			auto j = cur.front();
			cur.pop();
			d.push_back(j);
			for (auto z : adj2[j]) {
				deg[z]--;
				if (deg[z] == 0) cur.push(z);
			}
		}
		if ((int)d.size() != m) {
			cout << "No\n";
		} else {
			cout << "Yes\n";
		}
	}
}

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 12 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23