oj.uz

Submission #518471

# Submission time Handle Problem Language Result Execution time Memory
518471 2022-01-23T21:23:58 Z Alex_tz307 Mecho (IOI09_mecho) C++17
100 / 100
 202 ms 6208 KB 
#include <bits/stdc++.h>
#define INF 0x3f3f3f3f

using namespace std;

void testCase() {
  int n, s;
  cin >> n >> s;
  vector<string> a(n);
  queue<pair<int, int>> q;
  vector<vector<int>> bee(n, vector<int>(n, INF));
  int istart = -1, jstart = -1, istop = -1, jstop = -1;
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    for (int j = 0; j < n; ++j) {
      if (a[i][j] == 'H') {
        bee[i][j] = 0;
        q.emplace(i, j);
      } else if (a[i][j] == 'M') {
        istart = i, jstart = j;
      } else if (a[i][j] == 'D') {
        istop = i, jstop = j;
      }
    }
  }
  const int di[] = {-1, 0, 1, 0}, dj[] = {0, 1, 0, -1};
  auto valid = [&](const int &i, const int &j) -> bool {
    return 0 <= min(i, j) && max(i, j) < n && a[i][j] != 'T' && a[i][j] != 'H';
  };
  while (!q.empty()) {
    int i, j;
    tie(i, j) = q.front();
    q.pop();
    for (int k = 0; k < 4; ++k) {
      int iv = i + di[k], jv = j + dj[k];
      if (valid(iv, jv) && a[iv][jv] != 'D' && bee[iv][jv] == INF) {
        bee[iv][jv] = bee[i][j] + 1;
        q.emplace(iv, jv);
      }
    }
  }
  auto checkDistance = [&](const int &m, const int &b) -> bool {
    return m / s < b;
  };
  auto check = [&](const int &t) -> bool {
    vector<vector<int>> dp(n, vector<int>(n, INF));
    queue<pair<int, int>> q;
    dp[istart][jstart] = 0;
    q.emplace(istart, jstart);
    while (!q.empty()) {
      int i, j;
      tie(i, j) = q.front();
      q.pop();
      for (int k = 0; k < 4; ++k) {
        int iv = i + di[k], jv = j + dj[k];
        if (valid(iv, jv) && dp[iv][jv] == INF && checkDistance(dp[i][j] + 1, bee[iv][jv] - t)) {
          dp[iv][jv] = dp[i][j] + 1;
          q.emplace(iv, jv);
        }
      }
    }
    if (dp[istop][jstop] == INF) {
      return false;
    }
    return true;
  };
  int l = 0, r = bee[istart][jstart] - 1, ans = -1;
  while (l <= r) {
    int mid = (l + r) / 2;
    if (check(mid)) {
      ans = mid;
      l = mid + 1;
    } else {
      r = mid - 1;
    }
  }
  cout << ans << '\n';
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int tests = 1;
  for (int tc = 0; tc < tests; ++tc) {
    testCase();
  }
  return 0;
}

Subtask #1
100.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 83 ms 6104 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 0 ms 204 KB Output is correct
10 Correct 0 ms 204 KB Output is correct
11 Correct 0 ms 204 KB Output is correct
12 Correct 0 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 0 ms 204 KB Output is correct
16 Correct 1 ms 320 KB Output is correct
17 Correct 0 ms 204 KB Output is correct
18 Correct 0 ms 204 KB Output is correct
19 Correct 0 ms 204 KB Output is correct
20 Correct 0 ms 204 KB Output is correct
21 Correct 1 ms 332 KB Output is correct
22 Correct 0 ms 204 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 0 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 1 ms 332 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 6 ms 1468 KB Output is correct
34 Correct 5 ms 1416 KB Output is correct
35 Correct 18 ms 1412 KB Output is correct
36 Correct 7 ms 1740 KB Output is correct
37 Correct 7 ms 1740 KB Output is correct
38 Correct 26 ms 1792 KB Output is correct
39 Correct 9 ms 2160 KB Output is correct
40 Correct 10 ms 2168 KB Output is correct
41 Correct 37 ms 2176 KB Output is correct
42 Correct 16 ms 2616 KB Output is correct
43 Correct 12 ms 2584 KB Output is correct
44 Correct 40 ms 2612 KB Output is correct
45 Correct 13 ms 3036 KB Output is correct
46 Correct 15 ms 3040 KB Output is correct
47 Correct 49 ms 3044 KB Output is correct
48 Correct 15 ms 3568 KB Output is correct
49 Correct 18 ms 3616 KB Output is correct
50 Correct 70 ms 3596 KB Output is correct
51 Correct 18 ms 4180 KB Output is correct
52 Correct 20 ms 4152 KB Output is correct
53 Correct 70 ms 4128 KB Output is correct
54 Correct 21 ms 4788 KB Output is correct
55 Correct 23 ms 4776 KB Output is correct
56 Correct 80 ms 4740 KB Output is correct
57 Correct 26 ms 5388 KB Output is correct
58 Correct 29 ms 5408 KB Output is correct
59 Correct 94 ms 5392 KB Output is correct
60 Correct 28 ms 6180 KB Output is correct
61 Correct 31 ms 6116 KB Output is correct
62 Correct 115 ms 6064 KB Output is correct
63 Correct 114 ms 6164 KB Output is correct
64 Correct 202 ms 6160 KB Output is correct
65 Correct 201 ms 6056 KB Output is correct
66 Correct 137 ms 6140 KB Output is correct
67 Correct 121 ms 6072 KB Output is correct
68 Correct 49 ms 6092 KB Output is correct
69 Correct 43 ms 6116 KB Output is correct
70 Correct 42 ms 6116 KB Output is correct
71 Correct 34 ms 6092 KB Output is correct
72 Correct 35 ms 6208 KB Output is correct
73 Correct 35 ms 6128 KB Output is correct
74 Correct 66 ms 6096 KB Output is correct
75 Correct 62 ms 6104 KB Output is correct
76 Correct 62 ms 6112 KB Output is correct
77 Correct 63 ms 6120 KB Output is correct
78 Correct 74 ms 6104 KB Output is correct
79 Correct 59 ms 6124 KB Output is correct
80 Correct 62 ms 6108 KB Output is correct
81 Correct 68 ms 6120 KB Output is correct
82 Correct 58 ms 6092 KB Output is correct
83 Correct 77 ms 6100 KB Output is correct
84 Correct 66 ms 6104 KB Output is correct
85 Correct 65 ms 6088 KB Output is correct
86 Correct 86 ms 6104 KB Output is correct
87 Correct 77 ms 6148 KB Output is correct
88 Correct 81 ms 6096 KB Output is correct
89 Correct 80 ms 6092 KB Output is correct
90 Correct 83 ms 6084 KB Output is correct
91 Correct 82 ms 6068 KB Output is correct
92 Correct 84 ms 6076 KB Output is correct