제출 #944608

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
944608		Nhoksocqt1	가장 긴 여행 (IOI23_longesttrip)	C++17	5 / 100	184 ms	2156 KiB

longesttrip

#ifndef Nhoksocqt1
    #include "longesttrip.h"
#endif // Nhoksocqt1
#include<bits/stdc++.h>
using namespace std;

#define inf 0x3f3f3f3f
#define sz(x) int((x).size())
#define fi first
#define se second
typedef long long ll;
typedef pair<int, int> ii;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int Random(int l, int r) {
    return uniform_int_distribution<int>(l, r)(rng);
}

const int MAXN = 260;

#ifdef Nhoksocqt1

bitset<MAXN> adjp[MAXN], idA, idB, bsA, bsB;
struct Jury {
    int n, d;

    void init(int _n, int _d) {
        n = _n, d = _d;
        int u, v;
        bool check(0);
        while(cin >> u >> v) {
            adjp[u][v] = adjp[v][u] = 1;
            check = 1;
        }

        if(!check) {
            for (int i = 0; i < n; ++i) {
                for (int j = i + 1; j < n; ++j) {
                    for (int k = j + 1; k < n; ++k) {
                        int cnt = adjp[i][j] + adjp[i][k] + adjp[j][k];
                        if(cnt < d) {
                            vector<ii> p;
                            p.push_back(ii(i, j));
                            p.push_back(ii(i, k));
                            p.push_back(ii(j, k));

                            while(cnt < d) {
                                int r = Random(0, 2);
                                if(adjp[p[r].fi][p[r].se])
                                    continue;

                                ++cnt;
                                adjp[p[r].fi][p[r].se] = adjp[p[r].se][p[r].fi] = 1;
                            }
                        }
                    }
                }
            }
        }
    }

    bool are_connected(vector<int> &A, vector<int> &B) {
        bsA = bsB = idA = idB = 0;
        for (int it = 0; it < sz(A); ++it) {
            bsA |= adjp[A[it]];
            idA[A[it]] = 1;
        }

        for (int it = 0; it < sz(B); ++it) {
            bsB |= adjp[B[it]];
            idB[B[it]] = 1;
        }

        return ((bsA & idB).count() > 0 || (bsB & idA).count() > 0);
    }

} jury;

#endif // Nhoksocqt1

vector<int> A[MAXN];
int tr[MAXN], numNode;
bool adj[MAXN][MAXN], dx[MAXN];

bool check_are_connected(vector<int> &A, vector<int> &B) {
    #ifdef Nhoksocqt1
        return jury.are_connected(A, B);
    #else
        return are_connected(A, B);
    #endif // Nhoksocqt1
}

class DisjointSet {
    private:
        vector<int> lab;

    public:
        DisjointSet(int _n = 0) {
            lab.assign(_n + 7, -1);
        }

        int find(int u) {
            return (lab[u] < 0) ? u : (lab[u] = find(lab[u]));
        }

        bool join(int u, int v) {
            u = find(u), v = find(v);
            if(u == v)
                return (false);

            if(lab[u] > lab[v])
                swap(u, v);

            lab[u] += lab[v];
            lab[v] = u;
            return (true);
        }
} dsu;

ii dfsFar(int u, int p) {
    ii res = {0, u};
    for (int it = 0; it < sz(A[u]); ++it) {
        int v(A[u][it]);
        if(v != p) {
            ii tmp = dfsFar(v, u);
            tr[v] = u;

            ++tmp.fi;
            res = max(res, tmp);
        }
    }

    return res;
}

vector<int> longest_trip(int N, int D) {
    numNode = N;
    if(D == 3) {
        vector<int> ans;
        for (int i = 0; i < numNode; ++i)
            ans.push_back(i);

        return ans;
    }

    for (int i = 0; i < numNode; ++i)
        A[i].clear();

    vector<ii> edge;
    for (int u = 0; u < numNode; ++u) {
        for (int v = u + 1; v < numNode; ++v) {
            vector<int> A, B;
            A.push_back(u);
            B.push_back(v);
            adj[u][v] = adj[v][u] = check_are_connected(A, B);
            if(adj[u][v])
                edge.push_back(ii(u, v));
        }
    }

    dsu = DisjointSet(numNode);
    shuffle(edge.begin(), edge.end(), rng);
    for (int it = 0; it < sz(edge); ++it) {
        int u(edge[it].fi), v(edge[it].se);
        if(dsu.join(u, v)) {
            A[u].push_back(v);
            A[v].push_back(u);
        }
    }

    int x = dfsFar(0, -1).se;
    int y = dfsFar(x, -1).se;

    vector<int> ans;
    while(y != x) {
        ans.push_back(y);
        y = tr[y];
    }

    ans.push_back(x);
    return ans;
}

#ifdef Nhoksocqt1

int main(void) {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    #define TASK "longesttrip"
    if(fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }

    int n, d;
    cin >> n >> d;
    jury.init(n, d);

    vector<int> path = longest_trip(n, d);
    cout << "ANSWER: " << sz(path) << ": ";
    for (int it = 0; it < sz(path); ++it)
        cout << path[it] << ' '; cout << '\n';

    return 0;
}

#endif // Nhoksocqt1

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 25
• Subtask 4: 0 / 60