oj.uz

답안 #1042146

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1042146 2024-08-02T15:21:42 Z vjudge1 열대 식물원 (Tropical Garden) (IOI11_garden) C++17
100 / 100
 1311 ms 36180 KB 
#include "garden.h"
#include "gardenlib.h"
#include <bits/stdc++.h>
using namespace std;


void count_routes(int N, int M, int P, int R[][2], int Q, int G[]) {
  vector<vector<int>> adj(N);
  for (int i = 0; i < M; ++i) {
    adj[R[i][0]].push_back(R[i][1]);
    adj[R[i][1]].push_back(R[i][0]);
  }

  auto node = [&](int u, int v) {
    if (adj[v][0] == u)
      return N+v;
    else
      return v;
  };

  const int J = 29;
  vector<int> succ(2*N, -1);
  vector<int> indeg(2*N, 0);
  vector<vector<int>> rev(2*N);

  auto set_succ = [&](int u, int v) {
    succ[u] = v;
    rev[v].push_back(u);
    ++indeg[v];
  };

  for (int i = 0; i < N; ++i) {
    set_succ(node(-1, i), node(i, adj[i][0]));
    for (int v : adj[i]) {
      if (v != adj[i][0] or adj[i].size() == 1)
        set_succ(node(v, i), node(i, adj[i][0]));
      else
        set_succ(node(v, i), node(i, adj[i][1]));
    }
  }

  vector<int> lambda(2*N, -1);
  vector<int> mu(2*N, -1);

  auto floyd_cycle = [&](int u) {
    // cerr << "floyd " << u << endl;

    // buscamos dos elementos en un ciclo
    int a = succ[u];
    int b = succ[succ[u]];
    int i = 1;
    while (a != b) {
      if (mu[a] == 0) break;
      ++i;
      a = succ[a];
      b = succ[succ[b]];
    }

    if (mu[a] == 0) { // este ciclo ya lo hemos completado antes, no queremos repetir
      lambda[u] = lambda[a];
      mu[u] = i;
    }
    else {
      // ahora iteramos el ciclo para calcular su longitud
      b = succ[a];
      lambda[u] = 1; // longitud ciclo
      while (a != b) {
        ++lambda[u];
        b = succ[b];
      }
      // lambda[u] calculada

      // pasamos por todos los elementos del ciclo para guardar la informacion
      for (int i = 0; i < lambda[u]; ++i) {
        mu[a] = 0;
        lambda[a] = lambda[u];
        a = succ[a];
      }

      // reiniciamos punteros y ahora calculamos longitud de la cola e inicio del ciclo
      a = u;
      b = u;
      for (int i = 0; i < lambda[u]; ++i) {
        b = succ[b];
      }
      mu[u] = 0; // longitud cola 
      while (a != b) {
        ++mu[u];
        a = succ[a];
        b = succ[b];
      }
      // mu[u] calculada
    }

    // pasamos por los elementos de la cola para guardar la informacion
    a = succ[u];
    for (int i = 1; i < mu[u]; ++i) {
      mu[a] = mu[u] - i;
      lambda[a] = lambda[u];
      a = succ[a];
    }
  };

  // empezamos a hacer floyd por las hojas, para procesar colas eficientemente
  for (int u = 0; u < 2*N; ++u) {
    if (indeg[u] == 0) floyd_cycle(u);
  }

  // los que queden son ciclos puros
  for (int u = 0; u < 2*N; ++u) {
    if (mu[u] == -1) floyd_cycle(u);
  }

  auto get_rev_dists = [&](int u) {
    vector<int> dist(2*N, -1);
    queue<int> q;
    dist[u] = 0;
    q.push(u);
    while (not q.empty()) {
      int i = q.front(); q.pop();
      for (int j : rev[i]) {
        if (dist[j] == -1) {
          q.push(j);
          dist[j] = dist[i] + 1;
        }
      }
    }
    return dist;
  };

  auto can_reach = [&](int u, int v, int k, const vector<int>& dists) -> bool {
    if (dists[u] == -1) return false; // otra componenete
    if (k < dists[u]) return false; // no llegamos
    if (dists[u] == k) return true; // directamente
    if (mu[v] == 0 and (k - dists[u]) % lambda[v] == 0) // dando vueltas al ciclo
      return true; 
    return false;
  };

  vector<int> distP = get_rev_dists(P), distNP = get_rev_dists(N+P);

  for(int it = 0; it < Q; ++it) {
    int cnt = 0;
    for (int i = 0; i < N; ++i) {
      int u = node(-1, i);

      if (can_reach(u, P, G[it], distP) or can_reach(u, N+P, G[it], distNP))
        ++cnt;
    }

    answer(cnt);
  }
}

Compilation message

garden.cpp: In function 'void count_routes(int, int, int, int (*)[2], int, int*)':
garden.cpp:21:13: warning: unused variable 'J' [-Wunused-variable]
   21 |   const int J = 29;
      |             ^

Subtask #1
49.0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 ms 448 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 712 KB Output is correct
7 Correct 0 ms 436 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 856 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 ms 448 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 712 KB Output is correct
7 Correct 0 ms 436 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 856 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 18 ms 10372 KB Output is correct
13 Correct 31 ms 21592 KB Output is correct
14 Correct 69 ms 29572 KB Output is correct
15 Correct 75 ms 30060 KB Output is correct
16 Correct 54 ms 22100 KB Output is correct
17 Correct 53 ms 19820 KB Output is correct
18 Correct 34 ms 10320 KB Output is correct
19 Correct 68 ms 29580 KB Output is correct
20 Correct 75 ms 30292 KB Output is correct
21 Correct 117 ms 22100 KB Output is correct
22 Correct 54 ms 19640 KB Output is correct
23 Correct 67 ms 32336 KB Output is correct

Subtask #3
31.0 / 31.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 ms 448 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 712 KB Output is correct
7 Correct 0 ms 436 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 856 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 18 ms 10372 KB Output is correct
13 Correct 31 ms 21592 KB Output is correct
14 Correct 69 ms 29572 KB Output is correct
15 Correct 75 ms 30060 KB Output is correct
16 Correct 54 ms 22100 KB Output is correct
17 Correct 53 ms 19820 KB Output is correct
18 Correct 34 ms 10320 KB Output is correct
19 Correct 68 ms 29580 KB Output is correct
20 Correct 75 ms 30292 KB Output is correct
21 Correct 117 ms 22100 KB Output is correct
22 Correct 54 ms 19640 KB Output is correct
23 Correct 67 ms 32336 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 92 ms 7260 KB Output is correct
26 Correct 173 ms 10588 KB Output is correct
27 Correct 610 ms 21584 KB Output is correct
28 Correct 905 ms 29744 KB Output is correct
29 Correct 906 ms 30140 KB Output is correct
30 Correct 532 ms 22116 KB Output is correct
31 Correct 544 ms 19792 KB Output is correct
32 Correct 195 ms 10580 KB Output is correct
33 Correct 812 ms 29832 KB Output is correct
34 Correct 831 ms 30292 KB Output is correct
35 Correct 570 ms 22180 KB Output is correct
36 Correct 823 ms 19540 KB Output is correct
37 Correct 774 ms 32340 KB Output is correct
38 Correct 1311 ms 36180 KB Output is correct