Submission #486283

#	Time	Username	Problem	Language	Result	Execution time	Memory
486283		ez_ioi	Nautilus (BOI19_nautilus)	C++17	100 / 100	184 ms	1220 KiB

nautilus

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int mxN = 5e2 + 5, mod = 1e9 + 7, LOG = 20;

int r, c, m;

bool a[mxN][mxN];

bitset <mxN * mxN> A, B;

int main() {
	ios :: sync_with_stdio(false), cin.tie(nullptr);
	cin >> r >> c >> m;
	for (int i = 1; i <= r; ++i) {
		for (int j = 1; j <= c; ++j) {
			char b;
			cin >> b;
			a[i][j] = (b == '.');
			A[i * mxN + j] = B[i * mxN + j] = a[i][j];
		}
	}
	string s;
	cin >> s;
	for (int i = 0; i < m; ++i) {
		if (s[i] == 'S') A <<= mxN;
		else if (s[i] == 'N') A >>= mxN;
		else if (s[i] == 'W') A >>= 1;
		else if (s[i] == 'E') A <<= 1;
		else if (s[i] == '?') A = (A << mxN) | (A >> mxN) | (A >> 1) | (A << 1);
		A &= B; // only water parts should be remained
	}
	cout << A.count(); 
	return 0;
}

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