제출 #557540

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
557540		fatemetmhr	Political Development (BOI17_politicaldevelopment)	C++17	100 / 100	339 ms	41704 KiB

politicaldevelopment

// `Be name khoda` //

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define pb     push_back
#define all(x) x.begin(), x.end()
#define fi     first
#define se     second


const int maxn5 = 2e5 + 10;

set <int> adjset[maxn5];
vector <int> adj[maxn5], ver;
priority_queue <pair<int, int>> av;
bool ed[20][20], mark[maxn5], dp[1 << 20];
int cnt[maxn5];

inline int max_indep(){
    int n = ver.size();
    assert(n <= 10);
    memset(ed, false, sizeof ed);
    for(int i = 0; i < n; i++) for(int j = 0; j < n; j++)
        if(adjset[ver[i]].find(ver[j]) != adjset[ver[i]].end())
            ed[i][j] = true;
    dp[0] = true;
    int ans = 0;
    for(int mask = 1; mask < (1 << n); mask++){
        int v = -1;
        dp[mask] = true;
        for(int i = 0; i < n; i++) if((mask >> i)&1){
            if(v == -1){
                v = i;
                dp[mask] = dp[mask ^ (1 << i)];
            }
            else
                dp[mask] &= ed[v][i];
        }
        if(dp[mask])
            ans = max(ans, __builtin_popcount(mask));
    }
    return ans;
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);

    int n, k; cin >> n >> k;
    for(int i = 0; i < n; i++){
        int l; cin >> l;
        cnt[i] = l;
        while(l--){
            int a; cin >> a;
            adj[i].pb(a);
            adjset[i].insert(a);
            assert(a != i);
        }
        av.push({-cnt[i], i});
    }
    for(int i = 0; i < n; i++) for(auto u : adj[i])
        assert(adjset[u].find(i) != adjset[u].end());
    int ans = 0;
    for(int i = 0; i < n; i++){
        while(mark[av.top().se])
            av.pop();
        int v = av.top().se;
        av.pop();
        mark[v] = true;
        ver.clear();
        for(auto u : adj[v]) if(!mark[u]){
            cnt[u]--;
            av.push({-cnt[u], u});
            ver.pb(u);
        }
        ans = max(ans, max_indep() + 1);
    }
    cout << ans << endl;
}

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