Submission #907204

#	Time	Username	Problem	Language	Result	Execution time	Memory
907204		12345678	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	624 ms	275612 KiB

bitaro

#include <bits/stdc++.h>

using namespace std;

const int nx=1e5+5, kx=330;
int n, m, Q, a, b, sz, l, ans, x, idx[nx];
pair<int, int> mx[nx][kx];
vector<int> d[nx], rv[nx], vs(nx), dp(nx);
queue<int> q;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n>>m>>Q;
    for (int i=1; i<=m; i++) cin>>a>>b, d[a].push_back(b), rv[b].push_back(a);
    //for (int i=1; i<=n; i++) for (int j=0; j<kx; j++) mx[i][j]={-1, 0};
    for (int i=1; i<=n; i++)
    {
        for (auto v:rv[i]) idx[v]=0;
        for (int j=0; j<kx; j++)
        {
            pair<int, pair<int, int>> res={-1, {0, -1}};
            for (auto v:rv[i])
            {
                while (idx[v]<kx&&mx[v][idx[v]].first>=0&&vs[mx[v][idx[v]].second]) idx[v]++;
                if (idx[v]<kx&&mx[v][idx[v]].first>=0) 
                {
                    if (res.first<mx[v][idx[v]].first+1) res={mx[v][idx[v]].first+1, {mx[v][idx[v]].second, v}};
                }
            }
            if (res.first>=0) 
            {
                idx[res.second.second]++, vs[res.second.first]=1, q.push(res.second.first);
            }
            mx[i][j]={res.first, res.second.first};
        }
        for (int j=0; j<kx; j++) 
        {
            if (mx[i][j].first<0) {
                mx[i][j]={0, i};
                break;
            }
        }
        while (!q.empty()) vs[q.front()]=0, q.pop();
    }
    //for (int i=1; i<=n; i++) for (int j=0; j<5; j++) cout<<i<<' '<<j<<' '<<mx[i][j].first<<' '<<mx[i][j].second<<'\n';
    while (Q--)
    {
        cin>>l>>sz;
        for (int i=1; i<=sz; i++) cin>>x, q.push(x), vs[x]=1;
        if (sz<kx-1)
        {
            bool pt=0;
            for (int i=0; i<kx&&!pt; i++) if (mx[l][i].first>=0&&!vs[mx[l][i].second]) cout<<mx[l][i].first<<'\n', pt=1;
            if (!pt) cout<<-1<<'\n';
        }
        else
        {
            for (int i=1; i<=n; i++) dp[i]=INT_MIN;
            dp[l]=0;
            ans=-1;
            for (int i=l; i>=1; i--) 
            {
                for (auto v:d[i]) dp[i]=max(dp[i], dp[v]+1);
                if (!vs[i]) ans=max(ans, dp[i]);
            }
            for (int i=1; i<=n; i++) vs[i]=0;
            cout<<ans<<'\n';
        }
        while (!q.empty()) vs[q.front()]=0, q.pop();
    }
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86