Submission #764948

#	Time	Username	Problem	Language	Result	Execution time	Memory
764948		adrilen	Political Development (BOI17_politicaldevelopment)	C++17	100 / 100	257 ms	30084 KiB

politicaldevelopment

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ld = long double;
using arr = array<int, 2>;

constexpr int maxn = 5e4 + 5, maxk = 11;

bool visited[maxn] = { 0 };

set<int> adj[maxn];
int k;
int output = 1;


void dfs(int pos)
{
    // assert(!visited[pos]);
    assert((int)adj[pos].size() <= k);

    visited[pos] = true;
    vector <bitset<maxk>> v(adj[pos].size());
    int ii = 0; // Counts which place it is in the order of adj[pos]
    int iii;
    for (int i : adj[pos])
    {
        iii = 0;

        v[ii][ii] = true;

        for (int y : adj[pos])
        {
            if (i != y) {
                v[ii][iii] = adj[i].count(y);
            }   
            iii++;
        }
        ii++;
    }

    bitset<maxk> all;

    for (int i = 1; i < (1 << (adj[pos].size())); i++){

        all.set();

        for (size_t y = 0; y < adj[pos].size(); y++) {
            if (i & (1 << y)) all &= v[y];
        }
        // cout << i << " " << all << "\n";
        if (__builtin_popcount(i) == all.count()) output = max(output, __builtin_popcount(i) + 1);
    }

    for (int i : adj[pos]) adj[i].erase(pos); // Something with the deletion is fishy, since 

    for (int i : adj[pos]) if (!visited[i] && (int)adj[i].size() <= k) dfs(i); // We need this !visited[i]
}


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

    int n;
    cin >> n >> k;

    for (int i = 0; i < n; i++)
    {
        int a, b;
        cin >> a;

        for (int y = 0; y < a; y++)
        {
            cin >> b;
            adj[i].insert(b);
        }  
    }


    for (int i = 0; i < n; i++) if (!visited[i] && (int)adj[i].size() <= k) dfs(i);

    cout << output << "\n";

    // cerr << clock() / static_cast<double>(CLOCKS_PER_SEC) << "\n";
}

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