Submission #767608

#	Time	Username	Problem	Language	Result	Execution time	Memory
767608		1ne	Bosses (BOI16_bosses)	C++14	0 / 100	1 ms	468 KiB

bosses

/*
*  author : Apiram                  
*  created: 27.06.2023 03:25:28
*/

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

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	int n;cin>>n;
	vector<set<int>>adj(n);
	vector<vector<int>>rev_adj(n);
	for (int i = 0;i<n;++i){
		int k;cin>>k;
		for (int j = 0;j<k;++j){
			int x;cin>>x;
			--x;
			adj[x].insert(i);
			rev_adj[i].push_back(x);
		}
	}
	int pos = 1e9;
	for (int i = 0;i<n;++i){
		queue<int>q;
		vector<set<int>>bdj = adj;
		int curv = 1;
		int ans = 0;
		vector<int>visited(n,false);
		vector<int>depth(n,0);
		visited[i] = true;
		vector<vector<int>>nx(n);
		function<pair<int,int>(int)>dfs = [&](int u){
			pair<int,int> v = {1,0};
			for (auto x:nx[u]){
				auto vv = dfs(x);
				v.first+=vv.first;
				v.second+=vv.second;
			}
			v.second+=v.first;
			return v;
		};
		q.push(i);
		vector<int>cost(n,1);
		while(!q.empty()){
			auto u = q.front();
			q.pop();
			for (auto x:bdj[u]){
				if (!visited[x]){
					visited[x] = true;
					depth[x] = depth[u] + 1;
					nx[u].push_back(x);
					q.push(x);
					curv++;
					for (auto y:rev_adj[x]){
						bdj[y].erase(x);	
					}		
				}	
			}
		}
		if (curv == n){
			//cout<<'\n';
			pos = min(pos,dfs(i).second);
		}
	}
	cout<<pos<<'\n';	
	return 0;
}

Compilation message (stderr)

bosses.cpp: In function 'int main()':
bosses.cpp:29:7: warning: unused variable 'ans' [-Wunused-variable]
   29 |   int ans = 0;
      |       ^~~

• Subtask 1: 0 / 22
• Subtask 2: 0 / 45
• Subtask 3: 0 / 33