Submission #321064

#	Time	Username	Problem	Language	Result	Execution time	Memory
321064		nishuz	Collecting Mushrooms (NOI18_collectmushrooms)	C++14	18 / 100	19 ms	13036 KiB

mushrooms

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ll long long
#define ull unsigned long long
#define ld long double
#define F first
#define S second
#define eb emplace_back
#define pb push_back
#define mp make_pair
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

using namespace __gnu_pbds;
using namespace std;

template <typename T> using oset = tree <pair <T, T>, null_type, less <pair <T, T>>, rb_tree_tag, tree_order_statistics_node_update>;

template <typename T>
void ckmin(T& a, const T b) {a = min(a, b);}

template <typename T>
void ckmax(T& a, const T b) {a = max(a, b);}

template <typename T>
void print(vector <T> v) {
    for (T i : v) cout << i << " ";
    cout << '\n';
}

template <typename T>
void print(vector <vector <T>>& v) {
    for (vector <T>& vv : v) {
        for (T& i : vv)
            cout << i << " ";
        cout << '\n';
    }
}

template <typename T>
void read(vector <T>& v) {for (T& i : v) cin >> i;}

template <typename T>
void read(T&& t) {cin >> t;}

template <typename T, typename... Args>
void read(T&& t, Args&&... args)
{
    cin >> t;
    read(forward<Args>(args)...);
}

template <typename T>
void print(T&& t) {cout << t << '\n';}

template <typename T, typename... Args>
void print(T&& t, Args&&... args)
{
    cout << t << " ";
    print(forward<Args>(args)...);
}

void usaco(string name = "")
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    if(name.size())
    {
        freopen((name+".in").c_str(), "r", stdin);
        freopen((name+".txt").c_str(), "w", stdout);
    }
}

void solve()
{
    int r, c, d, k, ans = 0;
    cin >> r >> c >> d >> k;
    int diff[r+2][c+2], dp[r+2][c+2];
    char a[r+1][c+1];
    for (int i = 1; i <= r; ++i)
        for (int j = 1; j <= c; ++j)
            cin >> a[i][j];
    for (int i = 0; i <= r+1; ++i)
        for (int j = 0; j <= c+1; ++j)
            dp[i][j] = diff[i][j] = 0;
    auto valid = [&](int x, int y, int r, int c)
    {
        bool ok = 1;
        ok &= (x >= 0 && x <= r+1);
        ok &= (y >= 0 && y <= c+1);
        return ok;
    };
    for (int i = 1; i <= r; ++i)
    {
        for (int j = 1; j <= c; ++j)
        {
            if (a[i][j] == 'S')
            {
                if (valid(i-d, j-d, r, c)) ++diff[i-d][j-d];
                if (valid(i-d, j+d+1, r, c)) --diff[i-d][j+d+1];
                if (valid(i+d+1, j-d, r, c)) --diff[i+d+1][j-d];
                if (valid(i+d+1, j+d+1, r, c)) ++diff[i+d+1][j+d+1];
            }
        }
    }
    for (int i = 0; i <= r; ++i)
    {
        for (int j = 0; j <= c; ++j)
        {
            if (i) dp[i][j] += dp[i-1][j];
            if (j) dp[i][j] += dp[i][j-1];
            if (i && j) dp[i][j] -= dp[i-1][j-1];
            dp[i][j] += diff[i][j];
            if (i && j) ans += (dp[i][j] >= k && a[i][j] == 'M');
        }
    }
    print(ans);
}

int32_t main()
{
    usaco();
    int t = 1;
    while (t--) solve();
}

Compilation message (stderr)

mushrooms.cpp: In function 'void usaco(std::string)':
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((name+".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mushrooms.cpp:73:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   73 |         freopen((name+".txt").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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