Submission #1047118

#	Time	Username	Problem	Language	Result	Execution time	Memory
1047118		vjudge1	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	100 / 100	9 ms	13168 KiB

mushrooms

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, a) for (int i = 0; i < (a); ++i)
#define REPD(i, a) for (int i = (a) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
int N, M, D, K;

void process(void){
    cin >> N >> M >> D >> K;
    vector<vector<char>> A(N + 1, vector<char>(M + 1));
    vector<vector<int>> F(N + 1, vector<int>(M + 1));
    FOR(i, 1, N) FOR(j, 1, M) {
        cin >> A[i][j];
        if(A[i][j] != 'S') continue;
        int x1 = max(1LL, i - D);
        int y1 = max(1LL, j - D);
        int x2 = min(N, i + D);
        int y2 = min(M, j + D);
        F[x1][y1]++;
        if(y2 + 1 <= M)
            F[x1][y2 + 1]--;
        if(x2 + 1 <= N)
            F[x2 + 1][y1]--;
        if(x2 + 1 <= N && y2 + 1 <= M)
            F[x2 + 1][y2 + 1]++;
    }
    int ans = 0;
    FOR(i, 1, N) FOR(j, 1, M){
        F[i][j] += F[i - 1][j] + F[i][j - 1] - F[i - 1][j - 1];
        if(A[i][j] == 'M' && F[i][j] >= K) ++ans;
    }
    cout << ans;
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    process();
    return (0 ^ 0);
}

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