oj.uz

Submission #980679

# Submission time Handle Problem Language Result Execution time Memory
980679 2024-05-12T10:11:58 Z hieptk Race (IOI11_race) C++17
21 / 100
 3000 ms 32100 KB 
#include <iostream>
#include <vector>
#include <cmath>
#include <numeric>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <cstring>
#include <unordered_map>
#include <iomanip>
#include <queue>
#include <map>
#include <sstream>
#include <stack>
#include <bitset>
 
using ll = long long;
using ld = long double;
 
using namespace std;

const int nm = 200002;
const int inf = 1e9;

set<pair<int, int>> adj[nm];
int H[nm][2], L[nm];
int Res;

unordered_map<int, int> bfs(int i, int p, int n, int k) {
  queue<int> q;
  q.push(i);
  vector<pair<int, int>> d(n, {inf, inf});
  d[i] = {0, 0};
  unordered_map<int, int> res;
  res[0] = 0;
  while (q.size()) {
    int i = q.front();
    q.pop();
    for (auto [j, w]: adj[i]) {
      if (j == p) continue;
      if (d[j].second > d[i].second + 1) {
        d[j].first = d[i].first + w;
        d[j].second = d[i].second + 1;
        if (!res.count(d[j].first)) res[d[j].first] = d[j].second;
        else res[d[j].first] = min(res[d[j].first], d[j].second);
        if (d[j].second < Res && d[j].first < k) q.push(j);
      }
    }
  }
  return res;
}

void check(int root, int n, int k) {
  unordered_map<int, int> res;
  for (auto [j, w]: adj[root]) {
    auto resj = bfs(j, root, n, k);
    for (auto [cost, len]: resj) {
      if (cost + w > k) continue;
      if (cost + w == k) {
          Res = min(Res, len + 1);
      } else if (res.count(k - cost - w)) {
          Res = min(Res, res[k - cost - w] + len + 1);
      }
    }
    for (auto [cost, len]: resj) {
        if (cost + w > k) continue;
        if (res.count(cost + w)) {
          res[cost + w] = min(res[cost + w], len + 1);
        } else {
          res[cost + w] = len + 1;
        }
    }
  }
}

void dfs(int i, int p, unordered_map<int, pair<int, int>> &child) {
  int nchild = 1;
  int maxchild = 0;
  for (auto [j, w]: adj[i]) {
    if (j == p) continue;
    dfs(j, i, child);
    nchild += child[j].first;
    maxchild = max(maxchild, child[j].second);
  }
  child[i] = {nchild, maxchild};
}

int findCenter(int root, int n) {
  unordered_map<int, pair<int, int>> child;
  dfs(root, -1, child);
  int s = child[root].first;
  if (s == 1) return -1;
  for (auto [i, p]: child) {
    int maxsplit = max(p.second, s - p.first);
    if (maxsplit <= s / 2) return i;
  }
  return -1;
}

void remove(int u) {
  for (auto [j, w]: adj[u]) {
    adj[j].erase({u, w});
  }
}

void calc(int root, int n, int k) {
  int u = findCenter(root, n);
  // cout << "root " << root << " center " << u << "\n";
  if (u == -1) return;
  check(u, n, k);
  // cout << "root " << root << " center " << u << " " << Res << "\n";
  remove(u);
  for (auto [j, w]: adj[u]) {
    calc(j, n, k);
  }
}

int best_path(int n, int k, int H[][2], int L[]) {
    for (int i = 0; i < n - 1; ++i) {
        adj[H[i][0]].emplace(H[i][1], L[i]);
        adj[H[i][1]].emplace(H[i][0], L[i]);
    }
    Res = n + 1;
    calc(0, n, k);
    return Res < n ? Res : -1;
}
 
// int main() {
//     #ifdef LOCAL
//     freopen("input.txt", "r", stdin);
//     #endif
//     ios::sync_with_stdio(0);
//     cin.tie(0);
//     int n, k;
//     cin >> n >> k;
//     for (int i = 0; i < n - 1; ++i) cin >> H[i][0] >> H[i][1] >> L[i];
//     cout << best_path(n, k, H, L) << "\n";
// }

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 15704 KB Output is correct
2 Correct 4 ms 15708 KB Output is correct
3 Correct 4 ms 15676 KB Output is correct
4 Correct 4 ms 15960 KB Output is correct
5 Correct 3 ms 15704 KB Output is correct
6 Correct 4 ms 15960 KB Output is correct
7 Correct 4 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15708 KB Output is correct
10 Correct 3 ms 15708 KB Output is correct
11 Correct 3 ms 15708 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 4 ms 15704 KB Output is correct
14 Correct 4 ms 15704 KB Output is correct
15 Correct 4 ms 15704 KB Output is correct
16 Correct 4 ms 15708 KB Output is correct
17 Correct 4 ms 15708 KB Output is correct
18 Correct 4 ms 15708 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 15704 KB Output is correct
2 Correct 4 ms 15708 KB Output is correct
3 Correct 4 ms 15676 KB Output is correct
4 Correct 4 ms 15960 KB Output is correct
5 Correct 3 ms 15704 KB Output is correct
6 Correct 4 ms 15960 KB Output is correct
7 Correct 4 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15708 KB Output is correct
10 Correct 3 ms 15708 KB Output is correct
11 Correct 3 ms 15708 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 4 ms 15704 KB Output is correct
14 Correct 4 ms 15704 KB Output is correct
15 Correct 4 ms 15704 KB Output is correct
16 Correct 4 ms 15708 KB Output is correct
17 Correct 4 ms 15708 KB Output is correct
18 Correct 4 ms 15708 KB Output is correct
19 Correct 3 ms 15708 KB Output is correct
20 Correct 3 ms 15708 KB Output is correct
21 Correct 7 ms 15952 KB Output is correct
22 Correct 7 ms 15960 KB Output is correct
23 Correct 7 ms 15960 KB Output is correct
24 Correct 6 ms 15964 KB Output is correct
25 Correct 7 ms 15964 KB Output is correct
26 Correct 8 ms 15968 KB Output is correct
27 Correct 6 ms 15964 KB Output is correct
28 Correct 7 ms 15960 KB Output is correct
29 Correct 7 ms 15964 KB Output is correct
30 Correct 7 ms 15964 KB Output is correct
31 Correct 10 ms 15964 KB Output is correct
32 Correct 8 ms 15964 KB Output is correct
33 Correct 9 ms 15964 KB Output is correct
34 Correct 15 ms 15964 KB Output is correct
35 Correct 19 ms 15964 KB Output is correct
36 Correct 21 ms 15960 KB Output is correct
37 Correct 20 ms 16000 KB Output is correct
38 Correct 18 ms 15984 KB Output is correct

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 15704 KB Output is correct
2 Correct 4 ms 15708 KB Output is correct
3 Correct 4 ms 15676 KB Output is correct
4 Correct 4 ms 15960 KB Output is correct
5 Correct 3 ms 15704 KB Output is correct
6 Correct 4 ms 15960 KB Output is correct
7 Correct 4 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15708 KB Output is correct
10 Correct 3 ms 15708 KB Output is correct
11 Correct 3 ms 15708 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 4 ms 15704 KB Output is correct
14 Correct 4 ms 15704 KB Output is correct
15 Correct 4 ms 15704 KB Output is correct
16 Correct 4 ms 15708 KB Output is correct
17 Correct 4 ms 15708 KB Output is correct
18 Correct 4 ms 15708 KB Output is correct
19 Execution timed out 3061 ms 32100 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 57.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 15704 KB Output is correct
2 Correct 4 ms 15708 KB Output is correct
3 Correct 4 ms 15676 KB Output is correct
4 Correct 4 ms 15960 KB Output is correct
5 Correct 3 ms 15704 KB Output is correct
6 Correct 4 ms 15960 KB Output is correct
7 Correct 4 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15708 KB Output is correct
10 Correct 3 ms 15708 KB Output is correct
11 Correct 3 ms 15708 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 4 ms 15704 KB Output is correct
14 Correct 4 ms 15704 KB Output is correct
15 Correct 4 ms 15704 KB Output is correct
16 Correct 4 ms 15708 KB Output is correct
17 Correct 4 ms 15708 KB Output is correct
18 Correct 4 ms 15708 KB Output is correct
19 Correct 3 ms 15708 KB Output is correct
20 Correct 3 ms 15708 KB Output is correct
21 Correct 7 ms 15952 KB Output is correct
22 Correct 7 ms 15960 KB Output is correct
23 Correct 7 ms 15960 KB Output is correct
24 Correct 6 ms 15964 KB Output is correct
25 Correct 7 ms 15964 KB Output is correct
26 Correct 8 ms 15968 KB Output is correct
27 Correct 6 ms 15964 KB Output is correct
28 Correct 7 ms 15960 KB Output is correct
29 Correct 7 ms 15964 KB Output is correct
30 Correct 7 ms 15964 KB Output is correct
31 Correct 10 ms 15964 KB Output is correct
32 Correct 8 ms 15964 KB Output is correct
33 Correct 9 ms 15964 KB Output is correct
34 Correct 15 ms 15964 KB Output is correct
35 Correct 19 ms 15964 KB Output is correct
36 Correct 21 ms 15960 KB Output is correct
37 Correct 20 ms 16000 KB Output is correct
38 Correct 18 ms 15984 KB Output is correct
39 Execution timed out 3061 ms 32100 KB Time limit exceeded
40 Halted 0 ms 0 KB -