Submission #871321

#	Time	Username	Problem	Language	Result	Execution time	Memory
871321		vjudge1	Collecting Mushrooms (NOI18_collectmushrooms)	C++14	79 / 100	24 ms	28504 KiB

mushrooms

#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define faster ios_base::sync_with_stdio(0); cin.tie(0);
#define int long long
using namespace std;
using lli = long long;
using ld = long double;
using pii = pair <int, int>;
mt19937_64 Rand(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 1e6 + 1000;
const int maxm = 1e3 + 1000;
const int mod = 1e9 + 7;

lli n, m, k, d, a[maxm][maxm];
char s[maxm][maxm];

void ReadInput()
{
    cin >> m >> n >> d >> k;
    for (lli i = 1; i <= m; i ++)
    {
        for (lli j = 1; j <= n; j ++)
        {
            cin >> s[i][j];
            a[i][j] = a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1];
            if (s[i][j] == 'S')
            {
                a[i][j] ++;
            }
            //cout << a[i][j] << endl;
        }
    }
}
void Solve()
{
    lli cnt = 0;
    for (lli i = 1; i <= m; i ++)
    {
        for (lli j = 1; j <= n; j ++)
        {
            if (s[i][j] == 'M')
            {
                lli x = i - d - 1;
                if (x < 1) x = 0;
                lli y = j - d - 1;
                if (y < 1) y = 0;
                lli u = i + d;
                if (u > m) u = m;
                lli v = j + d;
                if (v > n) v = n;
                //return;
                lli sum = a[u][v] - a[u][y] - a[x][v] + a[x][y];
                //cout << u << " " << v << " " << a[u][v] << " " << a[u][y] << " " << a[x][v] << " " << a[x][y] << " " << sum << endl;
                //return;
                if (sum >= k)
                {
                    cnt ++;
                }
            }
        }
    }
    cout << cnt;
}
#define debug
#define taskname "A"
signed main(){
    faster
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    int tt = 1;
    //cin >> tt;
    while (tt--){
        ReadInput();
        Solve();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << signed(double(clock()) / CLOCKS_PER_SEC * 1000);
        timeout.close();
        #ifndef debug
        cerr << "Time elapsed: " << signed(double(clock()) / CLOCKS_PER_SEC * 1000) << "ms\n";
        #endif // debug
    }
}

Compilation message (stderr)

mushrooms.cpp: In function 'int main()':
mushrooms.cpp:71:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
mushrooms.cpp:72:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 18 / 18
• Subtask 4: 23 / 23
• Subtask 5: 19 / 19
• Subtask 6: 0 / 21