Submission #136004

#	Time	Username	Problem	Language	Result	Execution time	Memory
136004		popovicirobert	Political Development (BOI17_politicaldevelopment)	C++14	100 / 100	896 ms	29048 KiB

politicaldevelopment

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44


/*const int MOD = (int) 1e9 + 7;

inline int lgput(int a, int b) {
    int ans = 1;
    while(b > 0) {
        if(b & 1) ans = (1LL * ans * a) % MOD;
        b >>= 1;
        a = (1LL * a * a) % MOD;
    }
    return ans;
}

inline void mod(int &x) {
    if(x >= MOD)
        x -= MOD;
}

inline void add(int &x, int y) {
    x += y;
    mod(x);
}

inline void sub(int &x, int y) {
    x += MOD - y;
    mod(x);
}

inline void mul(int &x, int y) {
    x = (1LL * x * y) % MOD;
}*/

/*int fact[], invfact[];

inline void prec(int n) {
    fact[0] = 1;
    for(int i = 1; i <= n; i++) {
        fact[i] = (1LL * fact[i - 1] * i) % MOD;
    }
    invfact[n] = lgput(fact[n], MOD - 2);
    for(int i = n - 1; i >= 0; i--) {
        invfact[i] = (1LL * invfact[i + 1] * (i + 1)) % MOD;
    }
}

inline int comb(int n, int k) {
    if(n < k) return 0;
    return (1LL * fact[n] * (1LL * invfact[k] * invfact[n - k] % MOD)) % MOD;
}*/

using namespace std;

const int MAXN = 50000;

set <int> g[MAXN + 1];
bool vis[MAXN + 1];

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, n, k;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> k;

    for(i = 1; i <= n; i++) {
        int sz;
        cin >> sz;
        while(sz--) {
            int nod;
            cin >> nod;
            g[i].insert(nod + 1);
        }
    }

    set < pair <int, int> > Q;
    for(i = 1; i <= n; i++) {
        Q.insert({g[i].size(), i});
    }

    int ans = 1;
    while(Q.size()) {
        int nod = Q.begin() -> second;
        Q.erase(Q.begin());

        vector <int> nodes;
        for(auto it : g[nod]) {
            nodes.push_back(it);
        }

        int sz = nodes.size();
        for(int conf = 0; conf < (1 << sz); conf++) {
            int num = __builtin_popcount(conf);
            if(num >= k || num < ans) {
                continue;
            }

            vector <int> cur;
            for(i = 0; i < sz; i++) {
                if(conf & (1 << i)) {
                    vis[nodes[i]] = 1;
                    cur.push_back(nodes[i]);
                }
            }

            bool ok = 1;
            for(auto it : cur) {
                for(auto itr : cur) {
                    if(it != itr && g[it].find(itr) == g[it].end()) {
                        ok = 0;
                        break;
                    }
                }
                if(!ok) {
                    break;
                }
            }

            if(ok) {
                ans = max(ans, num + 1);
            }

            for(auto it : cur) {
                vis[it] = 0;
            }
        }

        for(auto it : g[nod]) {
            Q.erase({g[it].size(), it});
            g[it].erase(nod);
            Q.insert({g[it].size(), it});
        }
    }

    cout << ans;

    return 0;
}

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