oj.uz

Submission #1035180

# Submission time Handle Problem Language Result Execution time Memory
1035180 2024-07-26T05:44:14 Z vjudge1 Tropical Garden (IOI11_garden) C
100 / 100
 1780 ms 9320 KB 
#include "garden.h"
#include "gardenlib.h"
#include <stdbool.h>
#include <string.h>
#include <assert.h>

int dsu_find(int *par, int a) {
  return par[a] < 0 ? a : (par[a] = dsu_find(par, par[a]));
}

void dsu_union(int *par, int a, int b) {
  a = dsu_find(par, a);
  b = dsu_find(par, b);
  assert(a != b); // we should only call dsu_union if they belong to different components
  if (-par[b] > -par[a]) {
    int tmp = a;
    a = b;
    b = tmp;
  }
  par[a] += par[b];
  par[b] = a;
}

void count_routes(int N, int M, int P, int R[][2], int Q, int G[]) {
  static int most_beautiful[150001][2];
  static int graph[300001];
  static int dsu[300001];
  static int rem[2][300001];
  int cyc[2];
  cyc[0] = cyc[1] = 1e9 + 1;
  memset(dsu, -1, sizeof dsu[0] * (2 * (size_t)N + 1));
  assert(dsu[2 * N] == -1);
  // 1 indexing, graph[u] == 0, means no edges connected to it
  P++;

  // save 2 most_beautiful edges
  for (int i = 0; i < M; i++) {
    for (int j = 0; j < 2; j++) {
      int u = R[i][j] + 1;
      int v = R[i][j^1] + 1;
      if (most_beautiful[u][0] == 0) {
        most_beautiful[u][0] = v;
      } else if (most_beautiful[u][1] == 0) {
        most_beautiful[u][1] = v;
      }
    }
  }

  // build functional graph
  for (int u = 1; u <= N; u++) {
    for (int j = 0; j < 2; j++) {
      int v = most_beautiful[u][j];
      if (most_beautiful[v][0] != u || most_beautiful[v][1] == 0)
        graph[u + j*N] = v;
      else
        graph[u + j*N] = v + N;
    }
  }

  // set everything in cycle
  for (int u = 1; u <= 2 * N; u++) {
    if (graph[u] == 0) continue;
    if (dsu_find(dsu, u) != dsu_find(dsu, graph[u])) {
      dsu_union(dsu, u, graph[u]);
      continue;
    }
    bool seen[2] = {false};
    int c = 0;
    int v = u;
    do {
      v = graph[v];
      seen[0] = seen[0] || v == P;
      seen[1] = seen[1] || v == P + N;
      rem[0][v] = rem[1][v] = -1;
      c++;
    } while (v != u);

    for (int i = 0; i < 2; i++) {
      if (!seen[i]) continue;
      cyc[i] = c;
      v = graph[P + i * N];
      for (int j = 1; j <= c; j++) {
        rem[i][v] = c - j;
        v = graph[v];
      }
      assert(v == graph[P + i * N]);
    }
  }
  
  // set everything out of cycle
  for (int i = 0; i < 2; i++) {
    int target = P + i * N;
    for (int u = 1; u <= N; u++) {
      if (rem[i][u] != 0 || u == target) continue;

      int v = u;
      int d = 0;
      do {
        rem[i][v] = -1;
        d++;
        v = graph[v];
      } while (rem[i][v] == 0 && v != target);

      if (v == target) {
        assert(rem[i][target] == -1 || rem[i][target] == 0);
        for (v = u; v != graph[target]; v = graph[v])
          rem[i][v] = d--;
        assert(d == -1);
        assert(rem[i][target] == 0);
      } else if (rem[i][v] > 0) {
        for (int w = u; w != v; w = graph[w])
          rem[i][w] = rem[i][v] + d--;
        assert(d == 0);
      }
    }
  }
  
  for (int i = 0; i < Q; i++) {
    int res = 0;
    for (int j = 0; j < 2; j++) {
      for (int k = 1; k <= N; k++) {
        if (rem[j][k] == -1) continue;
        res += rem[j][k] <= G[i] && (G[i] - rem[j][k]) % cyc[j] == 0;
      }
    }
    answer(res);
  }
}

Subtask #1
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 604 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 3 ms 1464 KB Output is correct
12 Correct 8 ms 2652 KB Output is correct
13 Correct 13 ms 5340 KB Output is correct
14 Correct 24 ms 7244 KB Output is correct
15 Correct 25 ms 7576 KB Output is correct
16 Correct 22 ms 5724 KB Output is correct
17 Correct 21 ms 5276 KB Output is correct
18 Correct 9 ms 2908 KB Output is correct
19 Correct 26 ms 8400 KB Output is correct
20 Correct 25 ms 8596 KB Output is correct
21 Correct 22 ms 6492 KB Output is correct
22 Correct 23 ms 5980 KB Output is correct
23 Correct 24 ms 8020 KB Output is correct

Subtask #3
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 3 ms 1464 KB Output is correct
12 Correct 8 ms 2652 KB Output is correct
13 Correct 13 ms 5340 KB Output is correct
14 Correct 24 ms 7244 KB Output is correct
15 Correct 25 ms 7576 KB Output is correct
16 Correct 22 ms 5724 KB Output is correct
17 Correct 21 ms 5276 KB Output is correct
18 Correct 9 ms 2908 KB Output is correct
19 Correct 26 ms 8400 KB Output is correct
20 Correct 25 ms 8596 KB Output is correct
21 Correct 22 ms 6492 KB Output is correct
22 Correct 23 ms 5980 KB Output is correct
23 Correct 24 ms 8020 KB Output is correct
24 Correct 1 ms 344 KB Output is correct
25 Correct 70 ms 1692 KB Output is correct
26 Correct 101 ms 2652 KB Output is correct
27 Correct 628 ms 5212 KB Output is correct
28 Correct 640 ms 7324 KB Output is correct
29 Correct 776 ms 7512 KB Output is correct
30 Correct 455 ms 5972 KB Output is correct
31 Correct 415 ms 5512 KB Output is correct
32 Correct 126 ms 2908 KB Output is correct
33 Correct 624 ms 8280 KB Output is correct
34 Correct 692 ms 8532 KB Output is correct
35 Correct 489 ms 6488 KB Output is correct
36 Correct 751 ms 5980 KB Output is correct
37 Correct 531 ms 8020 KB Output is correct
38 Correct 1780 ms 9320 KB Output is correct