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Submission #577571

# Submission time Handle Problem Language Result Execution time Memory
577571 2022-06-15T05:32:09 Z ThinGarfield Tracks in the Snow (BOI13_tracks) C++11
100 / 100
 1389 ms 130956 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define mp make_pair
#define F first
#define S second

constexpr int maxn = 4000;

int h, w;
char grid[maxn][maxn];

int dist[maxn][maxn];
pii dir[4] = {mp(1, 0), mp(-1, 0), mp(0, 1), mp(0, -1)};
deque<pii> q;

pii vsum(pii a, pii b) { return mp(a.F + b.F, a.S + b.S); }

int main() {
  // ios_base::sync_with_stdio(false);
  // cin.tie(NULL);

  cin >> h >> w;

  for (int r = 0; r < h; r++) {
    for (int c = 0; c < w; c++) {
      cin >> grid[r][c];
      dist[r][c] = maxn * maxn;
    }
  }

  //   for (auto p : dir) cout << p.F << ' ' << p.S << '\n';

  dist[0][0] = 0;
  q.push_front(mp(0, 0));
  while (!q.empty()) {
    pii cell = q.front();
    q.pop_front();
    for (int i = 0; i < 4; i++) {
      pii nbr = vsum(cell, dir[i]);
      if (nbr.F < 0 || nbr.F >= h || nbr.S < 0 || nbr.S >= w) continue;
      if (grid[nbr.F][nbr.S] == '.') continue;
      int wgt = (grid[cell.F][cell.S] == grid[nbr.F][nbr.S] ? 0 : 1);
      //   cout << "checked " << cell.F << cell.S << " " << nbr.F << nbr.S << '\t' << wgt << '\n';
      if (dist[cell.F][cell.S] + wgt < dist[nbr.F][nbr.S]) {
        dist[nbr.F][nbr.S] = dist[cell.F][cell.S] + wgt;
        if (wgt == 1)
          q.push_back(nbr);
        else
          q.push_front(nbr);
      }
    }
  }
  int ans = 0;
  for (int i = 0; i < h; i++) {
    for (int j = 0; j < w; j++) {
      //   cout << (dist[i][j] == maxn * maxn ? -1 : dist[i][j]) << '\t';
      if (grid[i][j] != '.') ans = max(ans, dist[i][j]);
    }
    // cout << '\n';
  }
  cout << ans + 1 << '\n';

  return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 5464 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 596 KB Output is correct
4 Correct 16 ms 5076 KB Output is correct
5 Correct 7 ms 2900 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 724 KB Output is correct
9 Correct 1 ms 1108 KB Output is correct
10 Correct 6 ms 2584 KB Output is correct
11 Correct 4 ms 2112 KB Output is correct
12 Correct 9 ms 3028 KB Output is correct
13 Correct 8 ms 3004 KB Output is correct
14 Correct 8 ms 2916 KB Output is correct
15 Correct 24 ms 5460 KB Output is correct
16 Correct 24 ms 5352 KB Output is correct
17 Correct 21 ms 5248 KB Output is correct
18 Correct 15 ms 5076 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 31164 KB Output is correct
2 Correct 120 ms 17856 KB Output is correct
3 Correct 1073 ms 94200 KB Output is correct
4 Correct 263 ms 33520 KB Output is correct
5 Correct 603 ms 67880 KB Output is correct
6 Correct 1371 ms 107876 KB Output is correct
7 Correct 17 ms 32596 KB Output is correct
8 Correct 17 ms 31060 KB Output is correct
9 Correct 5 ms 684 KB Output is correct
10 Correct 3 ms 452 KB Output is correct
11 Correct 17 ms 31936 KB Output is correct
12 Correct 2 ms 1600 KB Output is correct
13 Correct 123 ms 17872 KB Output is correct
14 Correct 77 ms 11900 KB Output is correct
15 Correct 76 ms 13012 KB Output is correct
16 Correct 53 ms 6608 KB Output is correct
17 Correct 304 ms 36068 KB Output is correct
18 Correct 280 ms 35832 KB Output is correct
19 Correct 282 ms 33484 KB Output is correct
20 Correct 238 ms 31100 KB Output is correct
21 Correct 628 ms 70064 KB Output is correct
22 Correct 611 ms 67816 KB Output is correct
23 Correct 580 ms 56884 KB Output is correct
24 Correct 606 ms 69348 KB Output is correct
25 Correct 1177 ms 94196 KB Output is correct
26 Correct 969 ms 130956 KB Output is correct
27 Correct 1274 ms 121148 KB Output is correct
28 Correct 1373 ms 107884 KB Output is correct
29 Correct 1370 ms 106180 KB Output is correct
30 Correct 1389 ms 110184 KB Output is correct
31 Correct 1018 ms 73392 KB Output is correct
32 Correct 1312 ms 109516 KB Output is correct