oj.uz

답안 #1042150

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1042150 2024-08-02T15:24:00 Z izanbf 열대 식물원 (Tropical Garden) (IOI11_garden) C++14
100 / 100
 1260 ms 34132 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), 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), mu(2*N, -1);

  auto floyd_cycle = [&](int u) {
    // 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 1 ms 600 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 0 ms 604 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 604 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 1 ms 860 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 600 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 0 ms 604 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 604 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 1 ms 860 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 18 ms 9820 KB Output is correct
13 Correct 28 ms 20604 KB Output is correct
14 Correct 70 ms 27948 KB Output is correct
15 Correct 78 ms 28500 KB Output is correct
16 Correct 55 ms 20556 KB Output is correct
17 Correct 51 ms 18256 KB Output is correct
18 Correct 34 ms 9812 KB Output is correct
19 Correct 67 ms 27892 KB Output is correct
20 Correct 83 ms 28496 KB Output is correct
21 Correct 104 ms 20560 KB Output is correct
22 Correct 52 ms 18012 KB Output is correct
23 Correct 63 ms 30548 KB Output is correct

Subtask #3
31.0 / 31.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 600 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 0 ms 604 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 604 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 1 ms 860 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 18 ms 9820 KB Output is correct
13 Correct 28 ms 20604 KB Output is correct
14 Correct 70 ms 27948 KB Output is correct
15 Correct 78 ms 28500 KB Output is correct
16 Correct 55 ms 20556 KB Output is correct
17 Correct 51 ms 18256 KB Output is correct
18 Correct 34 ms 9812 KB Output is correct
19 Correct 67 ms 27892 KB Output is correct
20 Correct 83 ms 28496 KB Output is correct
21 Correct 104 ms 20560 KB Output is correct
22 Correct 52 ms 18012 KB Output is correct
23 Correct 63 ms 30548 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 94 ms 7020 KB Output is correct
26 Correct 172 ms 10020 KB Output is correct
27 Correct 594 ms 20560 KB Output is correct
28 Correct 920 ms 27964 KB Output is correct
29 Correct 894 ms 28504 KB Output is correct
30 Correct 510 ms 20560 KB Output is correct
31 Correct 517 ms 18324 KB Output is correct
32 Correct 217 ms 9808 KB Output is correct
33 Correct 869 ms 27988 KB Output is correct
34 Correct 878 ms 28500 KB Output is correct
35 Correct 576 ms 20548 KB Output is correct
36 Correct 844 ms 18004 KB Output is correct
37 Correct 720 ms 30752 KB Output is correct
38 Correct 1260 ms 34132 KB Output is correct