Submission #1015425

#	Time	Username	Problem	Language	Result	Execution time	Memory
1015425		phoenix	Nautilus (BOI19_nautilus)	C++17	100 / 100	211 ms	860 KiB

nautilus

#include <bits/stdc++.h>

using namespace std;

struct bitMatrix {
    bitset<500> a[500];
    int n, m;
    bitMatrix() {}
    bitMatrix(int n, int m) : n(n), m(m) {}
    bitMatrix(vector<vector<bool>> st) {
        n = (int)st.size();
        m = (int)st[0].size();
        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                a[i][j] = st[i][j];
    }
    void move_up() {
        for (int i = 0; i < n - 1; i++)     
            swap(a[i], a[i + 1]);
        a[n - 1].reset();
    }
    void move_down() {
        for (int i = n - 1; i > 0; i--)
            swap(a[i - 1], a[i]);
        a[0].reset();
    }
    void move_left() {
        for (int i = 0; i < n; i++)
            a[i] >>= 1; 
    }
    void move_right() {
        for (int i = 0; i < n; i++)
            a[i] <<= 1;
    }
    void print() {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++)
                cout << a[i][j];
            cout << '\n';
        }
        cout << '\n';
    }
};

bitMatrix OR(const bitMatrix &a, const bitMatrix &b) {
    assert(a.n == b.n && a.m == b.m);
    bitMatrix res = a;
    for (int i = 0; i < res.n; i++)
        res.a[i] = res.a[i] | b.a[i];
    return res;
}
bitMatrix AND(const bitMatrix &a, const bitMatrix &b) {
    assert(a.n == b.n && a.m == b.m);
    bitMatrix res = a;
    for (int i = 0; i < res.n; i++)
        res.a[i] = res.a[i] & b.a[i];
    return res;
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n, m, L;
    cin >> n >> m >> L;
    bitMatrix a(n, m);
    for (int i = 0; i < n; i++)
        for (int j = 0; j < m; j++) {
            char c;
            cin >> c;
            a.a[i][j] = (c == '.');
        }
    bitMatrix cur = a;

    for (int it = 0; it < L; it++) {
        char c;
        cin >> c;
        if (c == 'N') {
            cur.move_up();
            cur = AND(cur, a);
        }
        if (c == 'S') {
            cur.move_down();
            cur = AND(cur, a);
        }
        if (c == 'W') {
            cur.move_left();
            cur = AND(cur, a);
        }
        if (c == 'E') {
            cur.move_right();
            cur = AND(cur, a);
        }
        if (c == '?') {
            bitMatrix b(n, m), c;
            
            c = cur; 
            c.move_up();
            b = OR(b, c);
            
            c = cur;
            c.move_down();
            b = OR(b, c);

            c = cur; 
            c.move_left();
            b = OR(b, c);

            c = cur;
            c.move_right();
            b = OR(b, c);

            cur = AND(b, a);
        }
    }
    int ans = 0;
    for (int i = 0; i < n; i++)
        ans += cur.a[i].count();
    cout << ans;
}

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