Submission #1110306

#	Time	Username	Problem	Language	Result	Execution time	Memory
1110306		whatthemomooofun1729	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	472 ms	262144 KiB

dango_maker

#include <iostream>
#include <algorithm>
#include <utility>
#include <vector>
#include <stack>
#include <map>
#include <queue>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cstring>
#include <cmath>
#include <functional>
#include <cassert>
#include <iomanip>
#include <numeric>
#include <bitset>
#include <sstream>
#include <chrono>
#include <random>

#define ff first
#define ss second
#define PB push_back
#define sz(x) int(x.size())
#define rsz resize
#define fch(xxx, yyy) for (auto xxx : yyy) // abusive notation
#define all(x) (x).begin(),(x).end()
#define eps 1e-9

// more abusive notation (use at your own risk):
// #define int ll

using namespace std;
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vi = vector<int>;
using vll = vector<ll>;

// debugging
void __print(int x) {std::cerr << x;}
void __print(ll x) {std::cerr << x;} /* remember to uncomment this when not using THE MACRO */
void __print(unsigned x) {std::cerr << x;}
void __print(ull x) {std::cerr << x;}
void __print(float x) {std::cerr << x;}
void __print(double x) {std::cerr << x;}
void __print(ld x) {std::cerr << x;}
void __print(char x) {std::cerr << '\'' << x << '\'';}
void __print(const char *x) {std::cerr << '\"' << x << '\"';}
void __print(const string& x) {std::cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V> void __print(const pair<T, V> &x) {std::cerr << '{'; __print(x.ff); std::cerr << ", "; __print(x.ss); std::cerr << '}';}
template<typename T> void __print(const T& x) {int f = 0; std::cerr << '{'; for (auto &i: x) std::cerr << (f++ ? ", " : ""), __print(i); std::cerr << "}";}
void _print() {std::cerr << "]\n";}
template <typename T, typename... V> void _print(T t, V... v) {__print(t); if (sizeof...(v)) std::cerr << ", "; _print(v...);}
void println() {std::cerr << ">--------------------<" << endl;}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

// templates
template <class T> bool ckmin(T &a, const T &b) {return b<a ? a = b, 1 : 0;}
template <class T> bool ckmax(T &a, const T &b) {return b>a ? a = b, 1 : 0;}
template <class T> using gr = greater<T>;
template <class T> using vc = vector<T>;
template <class T> using p_q = priority_queue<T>;
template <class T> using pqg = priority_queue<T, vc<T>, gr<T>>;
template <class T1, class T2> using pr = pair<T1, T2>;
mt19937_64 rng_ll(chrono::steady_clock::now().time_since_epoch().count());
int rng(int M) {return (int)(rng_ll()%M);} /*returns any random number in [0, M) */

// const variables
constexpr int INF = (int)2e9;
constexpr int MOD = 998244353;
constexpr long double EPS = (ld)1e-10, PI = 3.1415926535;
constexpr ll LL_INF = (ll)3e18;
constexpr int mod = (int)1e9 + 7;
constexpr ll inverse = 500000004LL; // inverse of 2 modulo 1e9 + 7

void setIO(const string& str) {// fast input/output
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (str.empty()) return;
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
}

const int MAXN = int(3e3) + 5;
const int MAXD = 2 * MAXN + 1;
int N, M, D;
char grid[MAXN][MAXN];
int dp[MAXD][MAXN][3]; // 0 --> nothing, 1 --> vertical, 2 --> horizontal
int len[MAXD];
vc<pii> pts[MAXD];

int check(int x, int y) {
    return (x >= 0 && x < N && y >= 0 && y < M);
}

int dango(int x, int y, int dir) {
    if (dir & 1) { // dir == 1
        if (!check(x - 1, y) || !check(x + 1, y)) return 0;
        if (grid[x - 1][y] == 'R' && grid[x][y] == 'G' && grid[x + 1][y] == 'W') return 1;
        else return 0;
    } else { // dir == 2
        //debug(x, y, dir);
        if (!check(x, y - 1) || !check(x, y + 1)) return 0;
        if (grid[x][y - 1] == 'R' && grid[x][y] == 'G' && grid[x][y + 1] == 'W') return 1;
        else return 0;
    }
}

signed main() { // TIME YOURSELF !!!
    setIO("");
    cin >> N >> M;
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < M; ++j) {
            cin >> grid[i][j];
        }
    }
    D = N + M - 1;
    for (int i = 0; i < D; ++i) {
        int x = i, y = 0;
        while (x >= 0) {
            len[i] += check(x, y);
            if (check(x, y)) {
                pts[i].PB({x, y});
            }
            x--, y++;
        }
    }
    for (int i = 0; i < D; ++i) {
        dp[i][0][0] = 0;
        dp[i][0][1] = dango(pts[i][0].ff, pts[i][0].ss, 1);
        dp[i][0][2] = dango(pts[i][0].ff, pts[i][0].ss, 2);
//        debug(i, len[i]);
//        debug("base case: ", dp[i][0][0], dp[i][0][1], dp[i][0][2]);
        for (int j = 1; j < len[i]; ++j) {
//            debug(j, dp[i][j-1][0], dp[i][j-1][1], dp[i][j-1][2]);
//            debug(pts[i][j]);
            dp[i][j][0] = max({dp[i][j-1][0], dp[i][j-1][1], dp[i][j-1][2]});
            if (dango(pts[i][j].ff, pts[i][j].ss, 1)) {
                dp[i][j][1] = max(dp[i][j-1][0], dp[i][j-1][1]) + 1;
            }
            if (dango(pts[i][j].ff, pts[i][j].ss, 2)) {
                dp[i][j][2] = max(dp[i][j-1][0], dp[i][j-1][2]) + 1;
            }
        }
    }
    int ans = 0;
    for (int i = 0; i < D; ++i) {
        //debug(i, len[i], dp[i][len[i] - 1][0], dp[i][len[i] - 1][1], dp[i][len[i] - 1][2]);
        ans += max({dp[i][len[i] - 1][0], dp[i][len[i] - 1][1], dp[i][len[i] - 1][2]});
    }
    cout << ans;
    return 0;
}

// TLE -> TRY NOT USING DEFINE INT LONG LONG
// CE -> CHECK LINE 45
// 5000 * 5000 size matrices are kinda big (potential mle)
// Do something, start simpler

Compilation message (stderr)

dango_maker.cpp: In function 'void setIO(const string&)':
dango_maker.cpp:89:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:90:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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