Submission #260448

#	Time	Username	Problem	Language	Result	Execution time	Memory
260448		dolphingarlic	Political Development (BOI17_politicaldevelopment)	C++14	100 / 100	1864 ms	24568 KiB

politicaldevelopment

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

set<int> graph[50000];
bool tried[50000];

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int n, k;
	cin >> n >> k;
	queue<int> q;
	for (int i = 0; i < n; i++) {
		int s;
		cin >> s;
		if (s < k) {
			tried[i] = true;
			q.push(i);
		}
		while (s--) {
			int b;
			cin >> b;
			graph[i].insert(b);
		}
	}

	int ans = 0;
	while (q.size()) {
		int curr = q.front();
		q.pop();

		for (int i = 0; i < (1 << graph[curr].size()); i++) {
			if (__builtin_popcount(i) <= ans) continue;
			vector<int> adj;
			int tmp = i;
			for (int j : graph[curr]) {
				if (tmp & 1) adj.push_back(j);
				tmp >>= 1;
			}
			bool good = true;
			for (int j = 0; j < adj.size(); j++) {
				for (int l = j + 1; l < adj.size(); l++) {
					good &= graph[adj[j]].find(adj[l]) != graph[adj[j]].end();
				}
			}
			if (good) ans = __builtin_popcount(i);
		}

		for (int i : graph[curr]) {
			graph[i].erase(curr);
			if (!tried[i] && graph[i].size() < k) {
				tried[i] = true;
				q.push(i);
			}
		}
		graph[curr].clear();
	}

	cout << ans + 1;
	return 0;
}

Compilation message (stderr)

politicaldevelopment.cpp: In function 'int main()':
politicaldevelopment.cpp:42:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int j = 0; j < adj.size(); j++) {
                    ~~^~~~~~~~~~~~
politicaldevelopment.cpp:43:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int l = j + 1; l < adj.size(); l++) {
                         ~~^~~~~~~~~~~~
politicaldevelopment.cpp:52:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (!tried[i] && graph[i].size() < k) {
                     ~~~~~~~~~~~~~~~~^~~

• Subtask 1: 4 / 4
• Subtask 2: 12 / 12
• Subtask 3: 23 / 23
• Subtask 4: 38 / 38
• Subtask 5: 23 / 23