Submission #1271003

#	Time	Username	Problem	Language	Result	Execution time	Memory
1271003		TrinhKhanhDung	Political Development (BOI17_politicaldevelopment)	C++20	100 / 100	304 ms	7288 KiB

politicaldevelopment

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(), v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define INF (ll)1e9
#define oo (ll)1e18
#define MOD (ll)(1e9 + 7)

using namespace std;

template<class T1, class T2>
    bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}

template<class T1, class T2>
    bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}

template<class T1, class T2>
    void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}

template<class T1, class T2>
    void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}

template<class T>
    void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}

void print(vector<pair<int, int>> v){
    for(auto x: v) cout << x.first << ' ' << x.second << '\n';
}

struct seg{
    vector<pair<int, int>> mi;
    int n;

    seg(int _n = 0){
        n = _n;
        mi.resize(4 * n, {0, 0});
    }

    void update(int p, int c){
        int i = 1, l = 0, r = n - 1;
        while(l < r){
            int m = (l + r) >> 1;
            if(p <= m){
                r = m;
                i = i * 2;
            }
            else{
                l = m + 1;
                i = i * 2 + 1;
            }
        }
        mi[i].first += c;
        mi[i].second = p;
        while(i > 1){
            i >>= 1;
            mi[i] = min(mi[i * 2], mi[i * 2 + 1]);
        }
    }
};

ll solve(){
    int n, k; cin >> n >> k;
    vector<vector<int>> adj(n);
    for(int i = 0; i < n; i++){
        int k; cin >> k;
        while(k--){
            int x; cin >> x;
            adj[i].push_back(x);
        }
        sort(adj[i].begin(), adj[i].end());
    }
    auto Find = [&](vector<int> &v, int c){
        int p = lower_bound(v.begin(), v.end(), c) - v.begin();
        if(p == (int)v.size() || v[p] != c) return false;
        return true;
    };
    auto check = [&](vector<int> &V){
        for(int i = 0; i < (int)V.size(); i++){
            int u = V[i];
            for(int j = i + 1; j < (int)V.size(); j++){
                int v = V[j];
                if(!Find(adj[u], v)) return false;
            }
        }
        return true;
    };
    seg it(n);
    for(int i = 0; i < n; i++){
        it.update(i, (int)adj[i].size());
    }
    vector<int> del(n);
    int ans = 1;
    for(int t = 0; t < n; t++){
        int u = it.mi[1].second;
        vector<int> V;
        for(int v: adj[u]){
            if(!del[v]) V.push_back(v);
        }
        for(int mask = 0; mask < MASK((int)V.size()); mask++){
            vector<int> V1;
            for(int i = 0; i < (int)V.size(); i++){
                if(BIT(mask, i)) V1.push_back(V[i]);
            }
            if(check(V1)) maximize(ans, __builtin_popcount(mask) + 1);
        }
        del[u] = true;
        it.update(u, INF);
        for(int v: adj[u]){
            it.update(v, -1);
        }
    }
    return ans;
    return 0;
}

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

    int t = 1;
//    cin >> t;
    while(t--){
        cout << solve() << '\n';
    }

    return 0;
}

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