Submission #719364

#	Time	Username	Problem	Language	Result	Execution time	Memory
719364		n0sk1ll	Political Development (BOI17_politicaldevelopment)	C++14	16 / 100	444 ms	60196 KiB

politicaldevelopment

#include <bits/stdc++.h>

#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);cerr.tie(0)
#define mp make_pair
#define xx first
#define yy second
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define all(x) x.begin(),x.end()
#define ff(i,a,b) for (int i = a; i < b; i++)
#define fff(i,a,b) for (int i = a; i <= b; i++)
#define bff(i,a,b) for (int i = b-1; i >= a; i--)
#define bfff(i,a,b) for (int i = b; i >= a; i--)

using namespace std;
long double typedef ld;
unsigned int typedef ui;
long long int typedef li;
pair<int,int> typedef pii;
pair<li,li> typedef pli;
pair<ld,ld> typedef pld;
vector<vector<int>> typedef graph;
unsigned long long int typedef ull;
//const int mod = 998244353;
const int mod = 1000000007;







//Note to self: Check for overflow

struct find_clique
{
    int g[12]; //graph by bitmask
    int dp1[35]; //first half
    int pc[35]; //precalced
    int dp2[35]; //second half

    void clear(int n)
    {
        ff(i,0,n) g[i]=0;
        ff(i,0,(1<<n)) dp1[i]=0;
        ff(i,0,(1<<n)) dp2[i]=0;
    }

    void add(int u, int v)
    {
        g[u]|=(1<<v);
        g[v]|=(1<<u);
    }

    /*int calc(int n)
    {

        int fh=n/2,sh=(n+1)/2,fb=(1<<fh)-1,sb=(1<<sh)-1;
        ff(i,0,(1<<sh)) pc[i]=__builtin_popcount(i);

        ff(mask,1,(1<<fh)) ff(j,0,fh) if (mask&(1<<j)) {
            dp1[mask]=max(dp1[mask],dp1[mask&g[j]]+1);
        }

        ff(mask,1,(1<<sh)) ff(j,0,sh) if (mask&(1<<j)) {
            dp2[mask]=max(dp2[mask],dp2[mask&(g[j]>>fh)]+1);
        }

        int ans=0;
        ff(mask,0,(1<<sh)) if (dp2[mask]==pc[mask])
        {
            int span=0;
            ff(j,0,sh) if (mask&(1<<j)) span|=(g[j]&fb);
            ans=max(ans,pc[mask]+dp1[span]);
        }

        return ans;
    }*/

    int calc(int n)
    {
        int ans=0;
        ff(mask,0,(1<<n))
        {
            bool dobar=true;
            ff(j,0,n) if (((g[j]|(1<<j))&mask)!=mask) dobar=false;
            if (dobar) ans=max(ans,__builtin_popcount(mask));
        }
        return ans;
    }
} ok;

set<pii> pq;
set<int> idemo[100005];

int main()
{
    FAST;

    int n,k; cin>>n>>k;
    ff(i,0,n)
    {
        int d; cin>>d;
        while (d--)
        {
            int x; cin>>x;
            idemo[i].insert(x);
            idemo[x].insert(i);
        }
    }
    ff(i,0,n) pq.insert({(int)idemo[i].size(),i});

    int ans=0;
    while (!pq.empty())
    {
        int p=pq.begin()->yy;

        vector<int> cvors;
        cvors.pb(p);

        for (auto it : idemo[p]) cvors.pb(it);

        /*cout<<"consider: ";
        for (auto it : cvors) cout<<it<<" "; cout<<endl;*/

        ok.clear((int)cvors.size());
        ff(i,0,(int)cvors.size())
            ff(j,i+1,(int)cvors.size())
                if (idemo[cvors[i]].count(cvors[j]))
                    ok.add(i,j);

        ans=max(ans,ok.calc((int)cvors.size()));

        for (auto it : idemo[p]) pq.erase({(int)idemo[it].size(),it}),idemo[it].erase(p),pq.insert({(int)idemo[it].size(),it});
        pq.erase({(int)idemo[p].size(),p});
    }

    cout<<ans<<"\n";
}

//Note to self: Check for overflow

/*

5 3
2 1 2
3 0 2 3
3 0 1 4
2 1 4
2 2 3

*/

• Subtask 1: 4 / 4
• Subtask 2: 12 / 12
• Subtask 3: 0 / 23
• Subtask 4: 0 / 38
• Subtask 5: 0 / 23