Submission #1057823

#	Time	Username	Problem	Language	Result	Execution time	Memory
1057823		manhlinh1501	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	247 ms	199256 KiB

dango_maker

#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
using i64 = long long;
const int MAXN = 3e3 + 5;

#define ALL(a) (a).begin(), (a).end()

#define R 0
#define D 1

int N, M;
char a[MAXN][MAXN];
int dp[MAXN][MAXN][2];
bool OK[MAXN][MAXN][2];
vector<pii> g[MAXN * 2];
int maxx[MAXN * 2];

bool check(int u, int v) {
    return (1 <= u and u <= N and 1 <= v and v <= M);
}

signed main() {
#define TASK "code"

    if (fopen(TASK ".inp", "r")) {
        freopen(TASK ".inp", "r", stdin);
        freopen(TASK ".out", "w", stdout);
    }

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    /// RGW
    cin >> N >> M;
    for(int i = 1; i <= N; i++) {
        for(int j = 1; j <= M; j++)
            cin >> a[i][j];
    }
    for(int i = 1; i <= N; i++) {
        for(int j = 1; j <= M; j++) {
            if(a[i][j] == 'R' and a[i][j + 1] == 'G' and a[i][j + 2] == 'W')
                OK[i][j][R] = true;
            if(a[i][j] == 'R' and a[i + 1][j] == 'G' and a[i + 2][j] == 'W')
                OK[i][j][D] = true;
        }
    }

    for(int i = 1; i <= N; i++) {
        for(int j = 1; j <= M; j++)
            g[i + j].emplace_back(i, j);
    }

    for(int i = 1; i <= N + M; i++)
        reverse(ALL(g[i]));

    for(int z = N + M; z >= 1; z--) {
        for(auto [u, v] : g[z]) {
//            printf("%d %d %d\n", z, u, v);
            dp[u][v][R] = dp[u + 1][v - 1][R];
            dp[u][v][D] = dp[u + 1][v - 1][D];
            if(OK[u][v][R])
                dp[u][v][R] = max(dp[u][v][R], max(dp[u + 1][v - 1][R], dp[u + 1][v - 1][D]) + 1);
            if(OK[u][v][D]) {
                dp[u][v][D] = max(dp[u][v][D], dp[u + 1][v - 1][D] + 1);
                if(v - 2 >= 1)
                    dp[u][v][D] = max(dp[u][v][D], dp[u + 2][v - 2][D] + 1);
                if(v - 3 >= 1)
                    dp[u][v][D] = max(dp[u][v][D], max(dp[u + 3][v - 3][D], dp[u + 3][v - 3][R]) + 1);
            }
            maxx[z] = max(maxx[z], max(dp[u][v][D], dp[u][v][R]));
        }
    }

    int ans = 0;
    for(int i = 1; i <= N + M; i++) {
//        cerr << maxx[i] << " ";
        ans += maxx[i];
    }
    cout << ans;

    return (0 ^ 0);
}

Compilation message (stderr)

dango_maker.cpp: In function 'int main()':
dango_maker.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |         freopen(TASK ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:28:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |         freopen(TASK ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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