Submission #1092917

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092917		juicy	Nautilus (BOI19_nautilus)	C++17	100 / 100	120 ms	784 KiB

nautilus

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

int main() {
  ios::sync_with_stdio(false); cin.tie(nullptr);

  int r, c, m; cin >> r >> c >> m;
  vector<bitset<500>> b(r), mp(r), nxt(r);
  for (int i = 0; i < r; ++i) {
    for (int j = 0; j < c; ++j) {
      char x; cin >> x;
      if (x == '.') {
        b[i].set(j);
        mp[i].set(j);
      }
    }
  }
  while (m--) {
    char c; cin >> c;
    for (int i = 0; i < r; ++i) {
      if (c == 'N') {
        if (i + 1 == r) {
          b[i].reset();
        } else {
          b[i] = b[i + 1] & mp[i];
        }
      } else if (c == 'W') {
        b[i] = b[i] >> 1 & mp[i];
      } else if (c == 'E') {
        b[i] = b[i] << 1 & mp[i];
      } else if (c == '?') {
        nxt[i].reset();
        nxt[i] = b[i] << 1 | b[i] >> 1;
        if (i) {
          nxt[i] |= b[i - 1];
        }
        if (i + 1 < r) {
          nxt[i] |= b[i + 1];
        }
        nxt[i] &= mp[i];
      }
    }
    if (c == 'S') {
      for (int i = r - 1; ~i; --i) {
        if (!i) {
          b[i].reset();
        } else {
          b[i] = b[i - 1] & mp[i];
        }
      }
    } else if (c == '?') {
      for (int i = 0; i < r; ++i) {
        b[i] = nxt[i];
      }
    }
  }
  int res = 0;
  for (int i = 0; i < r; ++i) {
    res += b[i].count();
  }
  cout << res;
  return 0;
}

• Subtask 1: 29 / 29
• Subtask 2: 37 / 37
• Subtask 3: 34 / 34