oj.uz

답안 #980700

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
980700 2024-05-12T10:30:36 Z hieptk 경주 (Race) (IOI11_race) C++17
100 / 100
 2408 ms 71352 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;

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

unordered_map<int, int> bfs(int i, int p, int k) {
  queue<int> q;
  q.push(i);
  unordered_map<int, pair<int, int>> d;
  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.count(j)) {
        d[j].first = d[i].first + w;
        d[j].second = d[i].second + 1;
        if (d[j].first <= k) {
          if (!res.count(d[j].first) || res[d[j].first] > d[j].second) 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 k) {
  unordered_map<int, int> res;
  for (auto [j, w]: adj[root]) {
    auto resj = bfs(j, root, 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] > len + 1) {
          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].first);
  }
  child[i] = {nchild, maxchild};
}

int findCenter(int root) {
  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 k) {
  int u = findCenter(root);
  // cout << "root " << root << " center " << u << "\n";
  if (u == -1) return;
  check(u, k);
  // cout << "root " << root << " center " << u << " " << Res << "\n";
  remove(u);
  for (auto [j, w]: adj[u]) {
    calc(j, 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;
    calc(0, 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

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 15708 KB Output is correct
2 Correct 5 ms 15708 KB Output is correct
3 Correct 4 ms 15708 KB Output is correct
4 Correct 4 ms 15708 KB Output is correct
5 Correct 4 ms 15708 KB Output is correct
6 Correct 3 ms 15964 KB Output is correct
7 Correct 3 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15704 KB Output is correct
10 Correct 4 ms 15704 KB Output is correct
11 Correct 3 ms 15704 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 3 ms 15708 KB Output is correct
14 Correct 4 ms 15708 KB Output is correct
15 Correct 3 ms 15708 KB Output is correct
16 Correct 3 ms 15704 KB Output is correct
17 Correct 3 ms 15808 KB Output is correct
18 Correct 3 ms 15704 KB Output is correct

Subtask #2
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 15708 KB Output is correct
2 Correct 5 ms 15708 KB Output is correct
3 Correct 4 ms 15708 KB Output is correct
4 Correct 4 ms 15708 KB Output is correct
5 Correct 4 ms 15708 KB Output is correct
6 Correct 3 ms 15964 KB Output is correct
7 Correct 3 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15704 KB Output is correct
10 Correct 4 ms 15704 KB Output is correct
11 Correct 3 ms 15704 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 3 ms 15708 KB Output is correct
14 Correct 4 ms 15708 KB Output is correct
15 Correct 3 ms 15708 KB Output is correct
16 Correct 3 ms 15704 KB Output is correct
17 Correct 3 ms 15808 KB Output is correct
18 Correct 3 ms 15704 KB Output is correct
19 Correct 3 ms 15708 KB Output is correct
20 Correct 4 ms 15704 KB Output is correct
21 Correct 5 ms 15964 KB Output is correct
22 Correct 5 ms 15960 KB Output is correct
23 Correct 5 ms 15964 KB Output is correct
24 Correct 5 ms 15964 KB Output is correct
25 Correct 5 ms 15964 KB Output is correct
26 Correct 5 ms 15976 KB Output is correct
27 Correct 4 ms 15964 KB Output is correct
28 Correct 5 ms 15964 KB Output is correct
29 Correct 5 ms 15964 KB Output is correct
30 Correct 5 ms 15964 KB Output is correct
31 Correct 5 ms 15964 KB Output is correct
32 Correct 5 ms 15964 KB Output is correct
33 Correct 6 ms 15964 KB Output is correct
34 Correct 5 ms 15800 KB Output is correct
35 Correct 6 ms 15964 KB Output is correct
36 Correct 6 ms 15964 KB Output is correct
37 Correct 6 ms 15964 KB Output is correct
38 Correct 6 ms 15964 KB Output is correct

Subtask #3
22.0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 15708 KB Output is correct
2 Correct 5 ms 15708 KB Output is correct
3 Correct 4 ms 15708 KB Output is correct
4 Correct 4 ms 15708 KB Output is correct
5 Correct 4 ms 15708 KB Output is correct
6 Correct 3 ms 15964 KB Output is correct
7 Correct 3 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15704 KB Output is correct
10 Correct 4 ms 15704 KB Output is correct
11 Correct 3 ms 15704 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 3 ms 15708 KB Output is correct
14 Correct 4 ms 15708 KB Output is correct
15 Correct 3 ms 15708 KB Output is correct
16 Correct 3 ms 15704 KB Output is correct
17 Correct 3 ms 15808 KB Output is correct
18 Correct 3 ms 15704 KB Output is correct
19 Correct 402 ms 31964 KB Output is correct
20 Correct 438 ms 32044 KB Output is correct
21 Correct 440 ms 32096 KB Output is correct
22 Correct 413 ms 32256 KB Output is correct
23 Correct 329 ms 31992 KB Output is correct
24 Correct 210 ms 32100 KB Output is correct
25 Correct 542 ms 36964 KB Output is correct
26 Correct 388 ms 41572 KB Output is correct
27 Correct 401 ms 46164 KB Output is correct
28 Correct 879 ms 64832 KB Output is correct
29 Correct 901 ms 63940 KB Output is correct
30 Correct 392 ms 46020 KB Output is correct
31 Correct 433 ms 46272 KB Output is correct
32 Correct 517 ms 46268 KB Output is correct
33 Correct 919 ms 46272 KB Output is correct
34 Correct 589 ms 46316 KB Output is correct

Subtask #4
57.0 / 57.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 15708 KB Output is correct
2 Correct 5 ms 15708 KB Output is correct
3 Correct 4 ms 15708 KB Output is correct
4 Correct 4 ms 15708 KB Output is correct
5 Correct 4 ms 15708 KB Output is correct
6 Correct 3 ms 15964 KB Output is correct
7 Correct 3 ms 15708 KB Output is correct
8 Correct 3 ms 15708 KB Output is correct
9 Correct 3 ms 15704 KB Output is correct
10 Correct 4 ms 15704 KB Output is correct
11 Correct 3 ms 15704 KB Output is correct
12 Correct 3 ms 15708 KB Output is correct
13 Correct 3 ms 15708 KB Output is correct
14 Correct 4 ms 15708 KB Output is correct
15 Correct 3 ms 15708 KB Output is correct
16 Correct 3 ms 15704 KB Output is correct
17 Correct 3 ms 15808 KB Output is correct
18 Correct 3 ms 15704 KB Output is correct
19 Correct 3 ms 15708 KB Output is correct
20 Correct 4 ms 15704 KB Output is correct
21 Correct 5 ms 15964 KB Output is correct
22 Correct 5 ms 15960 KB Output is correct
23 Correct 5 ms 15964 KB Output is correct
24 Correct 5 ms 15964 KB Output is correct
25 Correct 5 ms 15964 KB Output is correct
26 Correct 5 ms 15976 KB Output is correct
27 Correct 4 ms 15964 KB Output is correct
28 Correct 5 ms 15964 KB Output is correct
29 Correct 5 ms 15964 KB Output is correct
30 Correct 5 ms 15964 KB Output is correct
31 Correct 5 ms 15964 KB Output is correct
32 Correct 5 ms 15964 KB Output is correct
33 Correct 6 ms 15964 KB Output is correct
34 Correct 5 ms 15800 KB Output is correct
35 Correct 6 ms 15964 KB Output is correct
36 Correct 6 ms 15964 KB Output is correct
37 Correct 6 ms 15964 KB Output is correct
38 Correct 6 ms 15964 KB Output is correct
39 Correct 402 ms 31964 KB Output is correct
40 Correct 438 ms 32044 KB Output is correct
41 Correct 440 ms 32096 KB Output is correct
42 Correct 413 ms 32256 KB Output is correct
43 Correct 329 ms 31992 KB Output is correct
44 Correct 210 ms 32100 KB Output is correct
45 Correct 542 ms 36964 KB Output is correct
46 Correct 388 ms 41572 KB Output is correct
47 Correct 401 ms 46164 KB Output is correct
48 Correct 879 ms 64832 KB Output is correct
49 Correct 901 ms 63940 KB Output is correct
50 Correct 392 ms 46020 KB Output is correct
51 Correct 433 ms 46272 KB Output is correct
52 Correct 517 ms 46268 KB Output is correct
53 Correct 919 ms 46272 KB Output is correct
54 Correct 589 ms 46316 KB Output is correct
55 Correct 32 ms 17076 KB Output is correct
56 Correct 30 ms 16984 KB Output is correct
57 Correct 380 ms 32096 KB Output is correct
58 Correct 89 ms 32092 KB Output is correct
59 Correct 619 ms 43488 KB Output is correct
60 Correct 2408 ms 71352 KB Output is correct
61 Correct 539 ms 46016 KB Output is correct
62 Correct 739 ms 46232 KB Output is correct
63 Correct 759 ms 46120 KB Output is correct
64 Correct 2037 ms 47280 KB Output is correct
65 Correct 662 ms 46236 KB Output is correct
66 Correct 1813 ms 60356 KB Output is correct
67 Correct 379 ms 46092 KB Output is correct
68 Correct 611 ms 45800 KB Output is correct
69 Correct 584 ms 46056 KB Output is correct
70 Correct 506 ms 44992 KB Output is correct