Submission #374033

#	Time	Username	Problem	Language	Result	Execution time	Memory
374033		ritul_kr_singh	Bosses (BOI16_bosses)	C++17	67 / 100	1594 ms	1036 KiB

bosses

//#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define sp << " " <<
#define nl << "\n"

vector<vector<int>> g0, g1;
vector<bool> vis;

pair<int, int> dfs(int u){
    vis[u] = true;
    pair<int, int> res0 = {1, 0}, res1;
    for(int v : g1[u]){
        res1 = dfs(v);
        res0.second += res1.second;
        res0.first += res1.first;
    }
    res0.second += res0.first;
    return res0;
}

signed main(){
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    int n; cin >> n;
    g0.resize(n);
    for(int i=0; i<n; ++i){
        int k; cin >> k;
        for(int j=0; j<k; ++j){
            int x; cin >> x;
            g0[x-1].push_back(i);
        }
    }
    int ans = 1e18;
    for(int root=0; root<n; ++root){
        vis.assign(n, false);
        g1.assign(n, {});
        queue<int> q;
        q.push(root);
        vis[root] = true;
        while(!q.empty()){
            int u = q.front(); q.pop();
            for(int v : g0[u]){
                if(!vis[v]){
                    vis[v] = true;
                    q.emplace(v);
                    g1[u].push_back(v);
                }
            }
        }
        bool ok = true;
        for(int i=0; i<n; ++i) if(!vis[i]){
            ok = false;
        }
        if(ok) ans = min(ans, dfs(root).second);
    }
    cout << ans nl;
}

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