Submission #771918

#	Time	Username	Problem	Language	Result	Execution time	Memory
771918		GrindMachine	Political Development (BOI17_politicaldevelopment)	C++17	100 / 100	420 ms	28544 KiB

politicaldevelopment

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 5e4 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

set<int> adj[N];

void solve(int test_case)
{
    int n,k; cin >> n >> k;
    rep(i,n){
        int s; cin >> s;
        rep(j,s){
            int v; cin >> v;
            adj[i].insert(v);
        }
        adj[i].insert(i);
    }

    set<pii> st;
    rep(i,n){
        int d = sz(adj[i]);
        st.insert({d,i});
    }

    vector<bool> dp(1<<(k+1));
    int ans = 0;

    while(!st.empty()){
        auto [d,s] = *st.begin();
        st.erase(st.begin());

        assert(d <= k);
    
        vector<int> nodes(all(adj[s]));
        int siz = sz(nodes);
        fill(all(dp),0);
        dp[0] = 1;

        rep1(mask,(1<<siz)-1){
            int msb = -1;
            rev(bit,siz-1,0){
                if(mask & (1<<bit)){
                    msb = bit;
                    break;
                }
            }

            int u = nodes[msb];

            bool ok = true;
            rep(i,siz){
                if(mask & (1<<i)){
                    int v = nodes[i];
                    if(!adj[u].count(v)){
                        ok = false;
                        break;
                    }
                }
            }

            if(ok){
                dp[mask] = dp[mask^(1<<msb)];
            }
        }

        rep(mask,1<<siz){
            if(dp[mask]){
                int cnt = setbits(mask);
                amax(ans,cnt);
            }
        }

        trav(v,adj[s]){
            if(v == s) conts;
            int d2 = sz(adj[v]);
            st.erase({d2,v});
            adj[v].erase(s);
            d2--;
            st.insert({d2,v});
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

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