답안 #1042149

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1042149 2024-08-02T15:23:36 Z vjudge1 열대 식물원 (Tropical Garden) (IOI11_garden) C++17
100 / 100
1282 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;
      |             ^
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 1 ms 452 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 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 1 ms 600 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 1 ms 452 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 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 1 ms 600 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 19 ms 9784 KB Output is correct
13 Correct 27 ms 20568 KB Output is correct
14 Correct 78 ms 27984 KB Output is correct
15 Correct 75 ms 28532 KB Output is correct
16 Correct 54 ms 20568 KB Output is correct
17 Correct 52 ms 18260 KB Output is correct
18 Correct 36 ms 9808 KB Output is correct
19 Correct 66 ms 27984 KB Output is correct
20 Correct 82 ms 28504 KB Output is correct
21 Correct 100 ms 20564 KB Output is correct
22 Correct 53 ms 18008 KB Output is correct
23 Correct 67 ms 30552 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 1 ms 452 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 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 1 ms 600 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 8 ms 7004 KB Output is correct
12 Correct 19 ms 9784 KB Output is correct
13 Correct 27 ms 20568 KB Output is correct
14 Correct 78 ms 27984 KB Output is correct
15 Correct 75 ms 28532 KB Output is correct
16 Correct 54 ms 20568 KB Output is correct
17 Correct 52 ms 18260 KB Output is correct
18 Correct 36 ms 9808 KB Output is correct
19 Correct 66 ms 27984 KB Output is correct
20 Correct 82 ms 28504 KB Output is correct
21 Correct 100 ms 20564 KB Output is correct
22 Correct 53 ms 18008 KB Output is correct
23 Correct 67 ms 30552 KB Output is correct
24 Correct 1 ms 352 KB Output is correct
25 Correct 92 ms 6988 KB Output is correct
26 Correct 170 ms 10072 KB Output is correct
27 Correct 592 ms 20672 KB Output is correct
28 Correct 907 ms 28248 KB Output is correct
29 Correct 901 ms 28588 KB Output is correct
30 Correct 493 ms 20748 KB Output is correct
31 Correct 515 ms 18320 KB Output is correct
32 Correct 194 ms 9812 KB Output is correct
33 Correct 879 ms 27984 KB Output is correct
34 Correct 864 ms 28496 KB Output is correct
35 Correct 595 ms 20572 KB Output is correct
36 Correct 859 ms 18000 KB Output is correct
37 Correct 732 ms 30548 KB Output is correct
38 Correct 1282 ms 34132 KB Output is correct