Submission #1265827

#	Time	Username	Problem	Language	Result	Execution time	Memory
1265827		mingga	Nautilus (BOI19_nautilus)	C++20	100 / 100	86 ms	548 KiB

nautilus

// Author: caption_mingle
#include "bits/stdc++.h"

using namespace std;

#define ln "\n"
#define pb push_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define ll long long
const int mod = 1e9 + 7;
const int inf = 2e9;
int n, m, k, idd[150];

pair<int, int> d[4] = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};

bitset<505> f[2][505], a[505];

signed main() {
    cin.tie(0) -> sync_with_stdio(0);
    #define task ""
    if(fopen(task ".INP", "r")) {
        freopen(task ".INP", "r", stdin);
        freopen(task ".OUT", "w", stdout);
    }
    cin >> n >> m >> k;
    idd['N'] = 1;
    idd['S'] = 0;
    idd['E'] = 3;
    idd['W'] = 2;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            char c; cin >> c;
            f[0][i][j] = (c == '.');
            a[i][j] = f[0][i][j]; 
        }
    }
    string s; cin >> s;
    for(int t = 1; t <= k; t++) {
        char c = s[t - 1];
        int id = t & 1;
        if(c == '?') {
            for(int i = 1; i <= n; i++) {
                f[id][i] = (f[id ^ 1][i] >> 1) | (f[id ^ 1][i] << 1);
                if(i > 1) f[id][i] |= f[id ^ 1][i - 1];
                if(i < n) f[id][i] |= f[id ^ 1][i + 1];
                f[id][i] &= a[i];
            }
        } else if(c == 'N') {
            for(int i = 1; i < n; i++) {
                f[id][i] = f[id ^ 1][i + 1] & a[i];
            }
            f[id][n].reset();
        } else if(c == 'S') {
            f[id][1].reset();
            for(int i = 2; i <= n; i++) {
                f[id][i] = f[id ^ 1][i - 1] & a[i];
            }
        } else if(c == 'E') {
            for(int i = 1; i <= n; i++) f[id][i] = (f[id ^ 1][i] << 1) & a[i]; 
        } else {
            for(int i = 1; i <= n; i++) f[id][i] = (f[id ^ 1][i] >> 1) & a[i];
        }
        // cerr << "STEP " << t << ln;
        // for(int i = 1; i <= n; i++) {
        //     for(int j = 1; j <= m; j++) {
        //         cerr << f[id][i][j];
        //     }
        //     cerr << ln;
        // }
    }
    int ans = 0;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            ans += f[k & 1][i][j];
        }
    }
    cout << ans << ln;
    cerr << "\nTime: " << clock() * 1000 / CLOCKS_PER_SEC;
}

Compilation message (stderr)

nautilus.cpp: In function 'int main()':
nautilus.cpp:25:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |         freopen(task ".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
nautilus.cpp:26:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |         freopen(task ".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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