Submission #679577

#	Time	Username	Problem	Language	Result	Execution time	Memory
679577		peijar	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	1152 ms	161696 KiB

tracks

#include <bits/stdc++.h>
#define int long long
using namespace std;

namespace std {
template <typename T> ostream &operator<<(ostream &out, const vector<T> &vec) {
  out << "[";
  for (int i = 0; i < (int)vec.size(); ++i) {
    out << vec[i];
    if (i + 1 < (int)vec.size())
      out << ", ";
  }
  return out << "]";
}
} // namespace std

void dbg_out() { cout << endl; }
template <typename Head, typename... Tail> void dbg_out(Head H, Tail... T) {
  cout << ' ' << H;
  dbg_out(T...);
}

#ifdef DEBUG
#define dbg(...) cout << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif

pair<int, int> DELTAS[] = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}};

signed main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(0);

  int nbLig, nbCol;
  cin >> nbLig >> nbCol;

  vector<vector<int>> grid(nbLig, vector<int>(nbCol, -1));
  for (int lig = 0; lig < nbLig; ++lig)
    for (int col = 0; col < nbCol; ++col) {
      char c;
      cin >> c;
      if (c == 'F')
        grid[lig][col] = 0;
      else if (c == 'R')
        grid[lig][col] = 1;
    }
  array<queue<pair<int, int>>, 2> files;

  files[grid[0][0]].emplace(0, 0);

  int sol = 0;

  auto isSafe = [&](int lig, int col) {
    return lig >= 0 and col >= 0 and lig < nbLig and col < nbCol and
           grid[lig][col] >= 0;
  };

  while (true) {
    int curVal = files[0].empty() ? 1 : 0;
    if (files[curVal].empty())
      break;
    sol++;

    while (!files[curVal].empty()) {
      auto [lig, col] = files[curVal].front();
      files[curVal].pop();
      for (auto [dlig, dcol] : DELTAS) {
        int l = lig + dlig, c = col + dcol;
        if (!isSafe(l, c))
          continue;
        files[grid[l][c]].emplace(l, c);
        grid[l][c] = -1;
      }
    }
  }
  cout << sol << endl;
}

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70