Submission #1042214

# Submission time Handle Problem Language Result Execution time Memory
1042214 2024-08-02T16:10:08 Z izanbf Tropical Garden (IOI11_garden) C++14
100 / 100
1463 ms 33364 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] != -1) break;
      ++i;
      a = succ[a];
      b = succ[succ[b]];
    }

    if (mu[a] != -1) { // a partir de <a> ya se ha calculado
      lambda[u] = lambda[a];
      mu[u] = i;

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

  // 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>& distv) -> bool {
    if (distv[u] == -1) return false; // otra componenete
    if (k < distv[u]) return false; // no llegamos
    if (distv[u] == k) return true; // directamente
    if (mu[v] == 0 and (k - distv[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;
      |             ^
# Verdict Execution time Memory Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 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 1 ms 348 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 1 ms 860 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 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 1 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 4780 KB Output is correct
12 Correct 19 ms 8208 KB Output is correct
13 Correct 28 ms 19032 KB Output is correct
14 Correct 80 ms 27052 KB Output is correct
15 Correct 88 ms 27476 KB Output is correct
16 Correct 60 ms 19436 KB Output is correct
17 Correct 67 ms 16956 KB Output is correct
18 Correct 19 ms 8028 KB Output is correct
19 Correct 72 ms 26896 KB Output is correct
20 Correct 82 ms 27476 KB Output is correct
21 Correct 93 ms 19284 KB Output is correct
22 Correct 55 ms 16944 KB Output is correct
23 Correct 87 ms 29536 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 1 ms 604 KB Output is correct
3 Correct 1 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 1 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 4780 KB Output is correct
12 Correct 19 ms 8208 KB Output is correct
13 Correct 28 ms 19032 KB Output is correct
14 Correct 80 ms 27052 KB Output is correct
15 Correct 88 ms 27476 KB Output is correct
16 Correct 60 ms 19436 KB Output is correct
17 Correct 67 ms 16956 KB Output is correct
18 Correct 19 ms 8028 KB Output is correct
19 Correct 72 ms 26896 KB Output is correct
20 Correct 82 ms 27476 KB Output is correct
21 Correct 93 ms 19284 KB Output is correct
22 Correct 55 ms 16944 KB Output is correct
23 Correct 87 ms 29536 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 119 ms 4984 KB Output is correct
26 Correct 249 ms 8236 KB Output is correct
27 Correct 630 ms 19144 KB Output is correct
28 Correct 1090 ms 27072 KB Output is correct
29 Correct 964 ms 27548 KB Output is correct
30 Correct 527 ms 19420 KB Output is correct
31 Correct 597 ms 17188 KB Output is correct
32 Correct 235 ms 7972 KB Output is correct
33 Correct 1074 ms 27060 KB Output is correct
34 Correct 967 ms 27532 KB Output is correct
35 Correct 605 ms 19476 KB Output is correct
36 Correct 852 ms 16984 KB Output is correct
37 Correct 1004 ms 29740 KB Output is correct
38 Correct 1463 ms 33364 KB Output is correct