Submission #1288751

#	Time	Username	Problem	Language	Result	Execution time	Memory
1288751		HiepVu217	Nautilus (BOI19_nautilus)	C++20	100 / 100	94 ms	724 KiB

nautilus

#include <bits/stdc++.h>
using namespace std;
const int N = 5e3 + 17;
int m, n, k, t[N], ans;
bitset <500> sea[N], f[N][7];
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> m >> n >> k;
    for (int i = 1; i <= m; ++i)
    {
        for (int j = n - 1; j >= 0; --j)
        {
            char c;
            cin >> c;
            sea[i][j] = (c == '.');
        }
    }
    for (int i = 1; i <= k; ++i)
    {
        char x;
        cin >> x;
        if (x == 'W')
        {
            t[i] = 0;
        }
        if (x == 'E')
        {
            t[i] = 1;
        }
        if (x == 'N')
        {
            t[i] = 2;
        }
        if (x == 'S')
        {
            t[i] = 3;
        }
        if (x == '?')
        {
            t[i] = 4;
        }
    }
    for (int i = 1; i <= m; ++i)
    {
        f[i][0] = sea[i];
    }
    for (int i = 1; i <= k; ++i)
    {
        int b = i & 1;
        if (t[i] == 0)
        {
            for (int i = 1; i <= m; ++i)
            {
                f[i][b] = (f[i][b ^ 1] << 1) & sea[i];
            }
            continue;
        }
        if (t[i] == 1)
        {
            for (int i = 1; i <= m; ++i)
            {
                f[i][b] = (f[i][b ^ 1] >> 1) & sea[i];
            }
            continue;
        }
        if (t[i] == 2)
        {
            for (int i = 1; i <= m; ++i)
            {
                f[i][b] = f[i + 1][b ^ 1] & sea[i];
            }
            continue;
        }
        if (t[i] == 3)
        {
            for (int i = 1; i <= m; ++i)
            {
                f[i][b] = f[i - 1][b ^ 1] & sea[i];
            }
            continue;
        }
        for (int i = 1; i <= m; ++i)
        {
            f[i][b] = (f[i][b ^ 1] << 1) | (f[i][b ^ 1] >> 1) | f[i + 1][b ^ 1] | f[i - 1][b ^ 1];
            f[i][b] &= sea[i];
        }
    }
    for (int i = 1; i <= m; ++i)
    {
        ans += f[i][k & 1].count();
    }
    cout << ans;
}

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