Submission #375687

#	Time	Username	Problem	Language	Result	Execution time	Memory
375687		valerikk	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	1886 ms	18540 KiB

dango_maker

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
//   R
//  RG
// RGW
// GW
// W

const int INF = 1e9;

int solve(vector<int> d, vector<int> r) {
    int n = d.size();
    vector<vector<int>> dp(3, vector<int>(3, -INF));
    dp[0][0] = 0;
    for (int i = 0; i < n; ++i) {
        vector<vector<int>> ndp(3, vector<int>(3, -INF));
        for (int x = 0; x < 3; ++x) {
            for (int y = 0; y < 3; ++y) {
                if (dp[x][y] == -INF) continue;
                for (int z = 0; z < 3; ++z) {
                    if (z == 1 && (x == 2 || y == 2 || !d[i])) continue;
                    if (z == 2 && !r[i]) continue;
                    ndp[y][z] = max(ndp[y][z], dp[x][y] + !!z);
                }
            }
        }
        dp = ndp;
    }
    int ans = 0;
    for (int i = 0; i < 3; ++i) {
        for (int j = 0; j < 3; ++j) ans = max(ans, dp[i][j]);
    }
    return ans;
}

int main() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
#endif
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    vector<vector<char>> grid(n, vector<char>(m));
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            cin >> grid[i][j];
        }
    }
    auto can_down = [&](int x, int y) {
        if (x + 2 < n && grid[x][y] == 'R' && grid[x + 1][y] == 'G' && grid[x + 2][y] == 'W') return 1;
        return 0;
    };
    auto can_right = [&](int x, int y) {
        if (y + 2 < m && grid[x][y] == 'R' && grid[x][y + 1] == 'G' && grid[x][y + 2] == 'W') return 1;
        return 0;
    };
    int ans = 0;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (i == n - 1 || j == 0) {
                vector<int> d, r;
                int curi = i, curj = j;
                while (curi >= 0 && curj < m) {
                    d.push_back(can_down(curi, curj));
                    r.push_back(can_right(curi, curj));
                    --curi;
                    ++curj;
                }
                ans += solve(d, r);
            }
        }
    }
    cout << ans << endl;
    return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 67 / 67