oj.uz

Submission #1108193

# Submission time Handle Problem Language Result Execution time Memory
1108193 2024-11-03T08:59:20 Z eym Race (IOI11_race) C++17
21 / 100
 3000 ms 14240 KB 
#include "race.h"

#include <cassert>
#include <cstdint>
#include <functional>
#include <unordered_map>
#include <vector>

using namespace std;

using i6 = int64_t;

struct Edge {
  int len;
  int dst;
};

vector<vector<Edge>> g;

int res = INT32_MAX;
int n;
int k;

vector<uint8_t> used;

struct CustomHash {
  // Seed with a fixed random value for consistency
  static uint64_t fixedRandom;
  size_t operator()(uint64_t x) const {
    // Use splitmix64 hash function
    x += fixedRandom;
    x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9ULL;
    x = (x ^ (x >> 27)) * 0x94d049bb133111ebULL;
    return x ^ (x >> 31);
  }
};

uint64_t CustomHash::fixedRandom = 1337;

int find_centroid(int root, int total_size) {
  vector<int> sizes(n);
  function<int(int, int)> find_sizes = [&](int p, int u) -> int {
    for (auto e : g[u]) {
      if (e.dst == p || used[e.dst])
        continue;
      sizes[u] += find_sizes(u, e.dst);
    }
    return sizes[u];
  };
  find_sizes(-1, root);

  function<int(int, int)> find_centroid_impl = [&](int p, int u) {
    for (auto e : g[u]) {
      if (e.dst == p || used[e.dst])
        continue;
      if (sizes[e.dst] > total_size / 2) {
        return find_centroid_impl(u, e.dst);
      }
    }
    return u;
  };

  return find_centroid_impl(-1, root);
}

void compute_solution(int root, int total_size) {
  if (used[root])
    return;

  int centroid = find_centroid(root, total_size);
  used[centroid] = 1;

  unordered_map<int, int> comp_sizes;

  {
    unordered_map<i6, int, CustomHash> min_depth_by_dist;
    unordered_map<i6, int, CustomHash> new_min_depth_by_dist;

    int comp_size = 0;
    function<void(int, int, int, i6)> walk = [&](int parent, int u, int depth, i6 dist) {
      comp_size++;
      if (dist > k || depth >= res)
        return;

      auto it = new_min_depth_by_dist.find(dist);
      if (it == new_min_depth_by_dist.end() || depth < it->second) {
        new_min_depth_by_dist[dist] = depth;
      }
      for (auto& e : g[u]) {
        if (e.dst == parent || used[e.dst])
          continue;
        walk(u, e.dst, depth + 1, dist + e.len);
      }
    };

    for (auto& e : g[centroid]) {
      if (used[e.dst])
        continue;
      comp_size = 0;
      new_min_depth_by_dist.clear();
      walk(centroid, e.dst, 1, e.len);
      comp_sizes[e.dst] = comp_size;
      for (auto& [dist, depth] : new_min_depth_by_dist) {
        if (depth >= res)
          continue;
        i6 rem_dist = k - dist;
        if (rem_dist == 0) {
          res = min(res, depth);
        } else if (rem_dist > 0) {
          auto it = min_depth_by_dist.find(rem_dist);
          if (it != min_depth_by_dist.end()) {
            res = min(res, depth + it->second);
          }
        }
      }
      for (auto& [dist, depth] : new_min_depth_by_dist) {
        auto it = min_depth_by_dist.find(dist);
        if (it == min_depth_by_dist.end() || depth < it->second) {
          min_depth_by_dist[dist] = depth;
        }
      }
    }
  }

  for (auto& e : g[centroid]) {
    compute_solution(e.dst, comp_sizes[e.dst]);
  }
}

int best_path(int N, int K, int H[][2], int L[]) {
  n = N;
  k = K;
  used.resize(N);
  g.resize(n);
  for (int i = 0; i < N; i++) {
    g[H[i][0]].push_back({L[i], H[i][1]});
    g[H[i][1]].push_back({L[i], H[i][0]});
  }
  compute_solution(0, n);
  return res == INT32_MAX ? -1 : res;
}

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2552 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 1 ms 2384 KB Output is correct
6 Correct 1 ms 2560 KB Output is correct
7 Correct 1 ms 2384 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 1 ms 2384 KB Output is correct
10 Correct 2 ms 2384 KB Output is correct
11 Correct 1 ms 2384 KB Output is correct
12 Correct 1 ms 2384 KB Output is correct
13 Correct 1 ms 2384 KB Output is correct
14 Correct 2 ms 2384 KB Output is correct
15 Correct 2 ms 2384 KB Output is correct
16 Correct 2 ms 2384 KB Output is correct
17 Correct 2 ms 2384 KB Output is correct
18 Correct 2 ms 2384 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2552 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 1 ms 2384 KB Output is correct
6 Correct 1 ms 2560 KB Output is correct
7 Correct 1 ms 2384 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 1 ms 2384 KB Output is correct
10 Correct 2 ms 2384 KB Output is correct
11 Correct 1 ms 2384 KB Output is correct
12 Correct 1 ms 2384 KB Output is correct
13 Correct 1 ms 2384 KB Output is correct
14 Correct 2 ms 2384 KB Output is correct
15 Correct 2 ms 2384 KB Output is correct
16 Correct 2 ms 2384 KB Output is correct
17 Correct 2 ms 2384 KB Output is correct
18 Correct 2 ms 2384 KB Output is correct
19 Correct 1 ms 2384 KB Output is correct
20 Correct 1 ms 2384 KB Output is correct
21 Correct 3 ms 2384 KB Output is correct
22 Correct 3 ms 2384 KB Output is correct
23 Correct 2 ms 2552 KB Output is correct
24 Correct 2 ms 2560 KB Output is correct
25 Correct 4 ms 2640 KB Output is correct
26 Correct 2 ms 2384 KB Output is correct
27 Correct 2 ms 2556 KB Output is correct
28 Correct 3 ms 2384 KB Output is correct
29 Correct 3 ms 2384 KB Output is correct
30 Correct 3 ms 2640 KB Output is correct
31 Correct 3 ms 2656 KB Output is correct
32 Correct 4 ms 2640 KB Output is correct
33 Correct 5 ms 2648 KB Output is correct
34 Correct 7 ms 2640 KB Output is correct
35 Correct 9 ms 2640 KB Output is correct
36 Correct 9 ms 2612 KB Output is correct
37 Correct 19 ms 2484 KB Output is correct
38 Correct 14 ms 2808 KB Output is correct

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2552 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 1 ms 2384 KB Output is correct
6 Correct 1 ms 2560 KB Output is correct
7 Correct 1 ms 2384 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 1 ms 2384 KB Output is correct
10 Correct 2 ms 2384 KB Output is correct
11 Correct 1 ms 2384 KB Output is correct
12 Correct 1 ms 2384 KB Output is correct
13 Correct 1 ms 2384 KB Output is correct
14 Correct 2 ms 2384 KB Output is correct
15 Correct 2 ms 2384 KB Output is correct
16 Correct 2 ms 2384 KB Output is correct
17 Correct 2 ms 2384 KB Output is correct
18 Correct 2 ms 2384 KB Output is correct
19 Correct 846 ms 9296 KB Output is correct
20 Correct 944 ms 9296 KB Output is correct
21 Correct 897 ms 9296 KB Output is correct
22 Correct 755 ms 9408 KB Output is correct
23 Correct 640 ms 10016 KB Output is correct
24 Correct 636 ms 9892 KB Output is correct
25 Execution timed out 3059 ms 14240 KB Time limit exceeded
26 Halted 0 ms 0 KB -

Subtask #4
0 / 57.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2552 KB Output is correct
2 Correct 1 ms 2384 KB Output is correct
3 Correct 1 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 1 ms 2384 KB Output is correct
6 Correct 1 ms 2560 KB Output is correct
7 Correct 1 ms 2384 KB Output is correct
8 Correct 1 ms 2384 KB Output is correct
9 Correct 1 ms 2384 KB Output is correct
10 Correct 2 ms 2384 KB Output is correct
11 Correct 1 ms 2384 KB Output is correct
12 Correct 1 ms 2384 KB Output is correct
13 Correct 1 ms 2384 KB Output is correct
14 Correct 2 ms 2384 KB Output is correct
15 Correct 2 ms 2384 KB Output is correct
16 Correct 2 ms 2384 KB Output is correct
17 Correct 2 ms 2384 KB Output is correct
18 Correct 2 ms 2384 KB Output is correct
19 Correct 1 ms 2384 KB Output is correct
20 Correct 1 ms 2384 KB Output is correct
21 Correct 3 ms 2384 KB Output is correct
22 Correct 3 ms 2384 KB Output is correct
23 Correct 2 ms 2552 KB Output is correct
24 Correct 2 ms 2560 KB Output is correct
25 Correct 4 ms 2640 KB Output is correct
26 Correct 2 ms 2384 KB Output is correct
27 Correct 2 ms 2556 KB Output is correct
28 Correct 3 ms 2384 KB Output is correct
29 Correct 3 ms 2384 KB Output is correct
30 Correct 3 ms 2640 KB Output is correct
31 Correct 3 ms 2656 KB Output is correct
32 Correct 4 ms 2640 KB Output is correct
33 Correct 5 ms 2648 KB Output is correct
34 Correct 7 ms 2640 KB Output is correct
35 Correct 9 ms 2640 KB Output is correct
36 Correct 9 ms 2612 KB Output is correct
37 Correct 19 ms 2484 KB Output is correct
38 Correct 14 ms 2808 KB Output is correct
39 Correct 846 ms 9296 KB Output is correct
40 Correct 944 ms 9296 KB Output is correct
41 Correct 897 ms 9296 KB Output is correct
42 Correct 755 ms 9408 KB Output is correct
43 Correct 640 ms 10016 KB Output is correct
44 Correct 636 ms 9892 KB Output is correct
45 Execution timed out 3059 ms 14240 KB Time limit exceeded
46 Halted 0 ms 0 KB -