Submission #591037

#	Time	Username	Problem	Language	Result	Execution time	Memory
591037		piOOE	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	229 ms	148492 KiB

dango_maker

//#define _GLIBCXX_DEBUG

//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

using namespace std;

//randoms
//chrono::steady_clock::now().time_since_epoch().count()
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

#define ll long long
#define trace(x) cout << #x << " = " << (x) << endl;
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define uniq(x) x.resize(unique(all(x)) -  begin(x))
#define ld long double
#define sz(s) (int) size(s)
#define pii pair<int, int>
#define mp(x, y) make_pair(x, y)
#define mt make_tuple
#define int128 __int128

template<typename T>
void ckmn(T &x, T y) { if (x > y) { x = y; }}

template<typename T>
void ckmx(T &x, T y) { if (x < y) { x = y; }}


int rand(int l, int r) { return (int) ((ll) rnd() % (r - l + 1)) + l; }

const ll infL = 1e18;
const int infI = 1e9 + 7;
const int N = 3000000;
const ll mod = 998244353;
const ld eps = 1e-9;

int g[N][3];
int used[N], pr[N], T;

bool dfs(int v) {
    if (used[v] == T) return false;
    used[v] = T;
    for (int to : g[v]) {
        if (to != -1 && pr[to] == -1) {
            pr[to] = v;
            return true;
        }
    }
    for (int to : g[v]) {
        if (to != -1 && dfs(pr[to])) {
            pr[to] = v;
            return true;
        }
    }
    return false;
}


int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<string> s(n);
    vector<vector<int>> R(n, vector<int>(m, -1));
    vector<vector<int>> D(n, vector<int>(m, -1));
    for (int i = 0; i < n; ++i) {
        cin >> s[i];
    }
    memset(g, -1, sizeof(g));
    int last = -1;
    for (int i = 1; i < n - 1; ++i) {
        for (int j = 0; j < m; ++j) {
            if (s[i][j] == 'G' && s[i - 1][j] == 'R' && s[i + 1][j] == 'W') {
                D[i][j] = D[i - 1][j] = D[i + 1][j] = ++last;
            }
        }
    }
    int gg = last;
    last = -1;
    for (int i = 0; i < n; ++i) {
        for (int j = 1; j < m - 1; ++j) {
            if (s[i][j] == 'G' && s[i][j - 1] == 'R' && s[i][j + 1] == 'W') {
                R[i][j] = R[i][j - 1] = R[i][j + 1] = ++last;
            }
        }
    }
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (D[i][j] != -1 && R[i][j] != -1) {

                g[D[i][j]][used[D[i][j]]++] = R[i][j];
            }
        }
    }
    memset(used, 0, sizeof(used));
    memset(pr, -1, sizeof(pr));
    int ans = 0;
    for (int i = 0; i <= gg; ++i) {
        ++T;
        if (dfs(i))
            ++ans;
    }
    cout << gg + last - ans + 2;
    return 0;
}

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