Submission #1198066

#	Time	Username	Problem	Language	Result	Execution time	Memory
1198066		Dan4Life	Political Development (BOI17_politicaldevelopment)	C++20	100 / 100	687 ms	312012 KiB

politicaldevelopment

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

#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a),end(a)

using ll = long long;
using vi = vector<int>;
using ar2 = array<int,2>;
using ar3 = array<int,3>;

const int mxN = (int)5e4+10;
const int INF = (int)1e9+1;
const ll LINF = (ll)2e18+1;
const int MOD = (int)1e9+7;

int N, K;
vi adj[mxN];
bitset<mxN> edge[mxN];
int cnt[mxN], bad[mxN];

int main(){
	ios_base::sync_with_stdio(false); cin.tie(0);
	cin >> N >> K;
	for(int i = 0; i < N; i++){
		int x,y; cin >> x; cnt[i]=x;
		while(x--){
			cin>>y; //if(y<x) continue;
			adj[i].pb(y),edge[i][y]=1;
		}
	}
	int ans = 1;
	vi xd(N,0);
	iota(all(xd),0);
	sort(all(xd),[&](int i, int j){
		return cnt[i]<cnt[j];
	});
	for(auto i : xd){
		vi xx; xx.clear();
		for(auto j : adj[i]) if(!bad[j])xx.pb(j);
		adj[i].swap(xx);
		for(int mask = 0; mask < (1<<sz(adj[i])); mask++){
			vi xd; int num = __builtin_popcount(mask);
			if(ans>=num+1 or num+1>K) continue;
			vi v; v.clear();
			bool ok = 1; v.pb(i);
			for(int j = 0; j < sz(adj[i]); j++){
				if(mask>>j&1){
					for(auto u : v)ok&=edge[u][adj[i][j]]&edge[adj[i][j]][u];
					if(!ok) break; v.pb(adj[i][j]); 
				}
			}
			if(ok) ans=num+1;
		}
		for(auto j : adj[i]) cnt[j]--;
		bad[i] = 1;
	}
	cout << ans << "\n";
}

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