Submission #710836

#	Time	Username	Problem	Language	Result	Execution time	Memory
710836		thimote75	Bitaro’s Party (JOI18_bitaro)	C++14	7 / 100	1827 ms	524288 KiB

bitaro

#include <bits/stdc++.h>

using namespace std;

#define idata vector<int>
#define igrid vector<idata>
#define di pair<int, int>

int nbNodes, nbRoads, nbQuery;
igrid roads;

const int BLOCK_SIZE = 400;

struct VBO {
    unordered_map<int, int> sdd_reverse;
    set<di, greater<>> sdd;

    void insert (int node, int depth) {
        if (sdd_reverse.find(node) != sdd_reverse.end()) {
            int max_depth = (*sdd_reverse.find(node)).second;
            if (max_depth >= depth) return ;

            sdd_reverse.erase(node);
            sdd.erase(di(max_depth, node));
        }
        
        sdd_reverse.insert(di(node, depth));
        sdd.insert(di(depth, node));

        if (sdd.size() <= BLOCK_SIZE) return ;
        auto it = sdd.end();
        it --;
        
        int rnode  = (*it).second;
        int rdepth = (*it).first;

        sdd_reverse.erase(rnode);
        sdd.erase(di(rdepth, rnode));
    }
    int query (set<int> &disabled) {
        for (di data : sdd) {
            if (disabled.find(data.second) != disabled.end()) continue ;

            return data.first;
        }

        return -1;
    }

    void merge (VBO &other) {
        for (di data : other.sdd)
            this->insert(data.second, data.first + 1);
    }
};

vector<VBO> vbos;
vector<int> bfs_v;
vector<int> dfs_v;
vector<int> visited;
int stage = 1;

void dfs (int node) {
    vbos[node].insert(node, 0);

    for (int prev : roads[node]) {
        if (vbos[node].sdd.size() == 0)
            dfs(prev);

        vbos[node].merge(vbos[prev]);
    }
}
void _c_dfs (int node) {
    if (visited[node] == stage) return ;
    visited[node] = stage;
    for (int prev : roads[node]) {
        dfs_v[prev] ++;

        _c_dfs(prev);
    }
}
int _compute (int start, set<int> &disabled) {
    queue<int> nodes;
    nodes.push(start);

    dfs_v.clear();
    dfs_v.resize(nbNodes, 0);
    _c_dfs(start);
    stage ++;

    bfs_v.clear();
    bfs_v.resize(nbNodes, -1);
    bfs_v[start] = 0;

    int answer = -1;
    while (nodes.size() != 0) {
        int curr = nodes.front();
        nodes.pop();
        
        if (disabled.find(curr) == disabled.end())
            answer = max(answer, bfs_v[curr]);

        for (int prev : roads[curr]) {
            dfs_v[prev] --;
            if (dfs_v[prev] != 0) continue ;
        
            bfs_v[prev] = bfs_v[curr] + 1;
            nodes.push(prev);
        }
    }

    return answer;
}
int compute (int node, set<int> &disabled) {
    if (disabled.size() <= BLOCK_SIZE)
        return vbos[node].query(disabled);
    
    return _compute(node, disabled);
}

int main () {
    cin >> nbNodes >> nbRoads >> nbQuery;
    vbos .resize(nbNodes);
    roads.resize(nbNodes);
    visited.resize(nbNodes);

    for (int idRoad = 0; idRoad < nbRoads; idRoad ++) {
        int a, b;
        cin >> a >> b;

        a --; b --;
        roads[b].push_back(a);
    }

    for (int idNode = 0; idNode < nbNodes; idNode ++) {
        if (vbos[idNode].sdd.size() != 0) continue ;

        dfs(idNode);
    }

    for (int idQuery = 0; idQuery < nbQuery; idQuery ++) {
        int target, dCount;
        cin >> target >> dCount;
        target --;

        set<int> disabled;
        for (int idD = 0; idD < dCount; idD ++) {
            int vd;
            cin >> vd;
            vd --;

            disabled.insert(vd);
        }

        cout << compute(target, disabled) << endl;
    }
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86