Submission #336524

#	Time	Username	Problem	Language	Result	Execution time	Memory
336524		Galebickosikasa	Dango Maker (JOI18_dango_maker)	C++17	33 / 100	386 ms	262148 KiB

dango_maker

// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx")
// #pragma comment(linker, "/stack:200000000"]
 
#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <unordered_set>
#include <unordered_map>
#include <set>
#include <map>
#include <queue>
#include <deque>
#include <bitset>
#include <stack>
#include <random>
#include <fstream>
#include <sstream>
#include <chrono>

#define fi first
#define se second
#define pb push_back
#define ll long long
#define ld long double
#define hm unordered_map 
#define pii pair<int, int>
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define cinv(v) for (auto& x: v) cin >> x
#define fr(i, n) for (int i = 0; i < n; ++i)
#define fl(i, l, n) for (int i = l; i < n; ++i)

// #define int ll

template <typename T1, typename T2> inline bool chkmin(T1 &x, const T2 &y) {if (x > y) {x = y; return 1;} return 0;}
template <typename T1, typename T2> inline bool chkmax(T1 &x, const T2 &y) {if (x < y) {x = y; return 1;} return 0;}

using namespace std;

#ifdef LOCAL
	#define dbg(x) cerr << #x << " : " << x << '\n'
	const int maxn = 20;
#else 
	#define dbg(x)
	const int maxn = 2e5 + 20;
#endif

//tg: @galebickosikasa
 
ostream& operator << (ostream& out, const pii& v) {
	out << v.fi << ", " << v.se;
	return out;
}

template<typename T> ostream& operator << (ostream& out, const vector<T>& v) {
    for (auto& x: v) out << x << " ";
    return out;
}

istream& operator >> (istream& in, pii& a) {
	in >> a.fi >> a.se;
	return in;
}

const ll inf = (ll) 2e9;
const ld pi = asin (1) * 2;
const ld eps = 1e-8;
const ll mod = (ll)1e9 + 7;
const ll ns = 97;

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

char goo[3000][3000];
int a[3000][3000];
int d[3000 * 3000 + 5], it[3000 * 3000 + 5];

struct edge {
	int to, f, c;
};

vector<int> g[3000 * 3000 + 10];
vector<edge> edges;

inline int bfs (int st, int fin) {
	for (int i = 0; i <= fin; ++i) d[i] = inf;
	d[st] = 0;
	queue<int> a;
	a.push (st);
	while (!a.empty ()) {
		int v = a.front ();
		a.pop ();
		for (auto& u: g[v]) {
			if (d[edges[u].to] == inf && edges[u].c - edges[u].f > 0) {
				d[edges[u].to] = d[v] + 1;
				a.push (edges[u].to);
			}
		}
	}
	return d[fin] < inf;
}

int dfs (int v, int t, int c = inf) {
	if (v == t) return c;
	while (it[v] < sz (g[v])) {
		auto& e = edges[g[v][it[v]]];
		if (d[e.to] == d[v] + 1 && e.c - e.f > 0) {
			int delta = dfs (e.to, t, min (c, e.c - e.f));
			if (delta > 0) {
				auto& _e = edges[g[v][it[v]] ^ 1];
				e.f += delta;
				_e.f -= delta;
				return delta;
			}
		}
		++it[v];
	}
	return 0;
}

signed main () {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
	int n, m;
	cin >> n >> m;
	for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) {
		cin >> goo[i][j];
	}
	for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) a[i][j] = -1;
	int c = 0;
	for (int i = 0; i < n; ++i) {
		for (int j = 2; j < m; ++j) {
			if (goo[i][j - 2] == 'R' && goo[i][j - 1] == 'G' && goo[i][j] == 'W') {
				a[i][j - 2] = a[i][j - 1] = a[i][j] = c++;
			}
		}
	}
	int last = c;
	for (int i = 2; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			if (goo[i - 2][j] == 'R' && goo[i - 1][j] == 'G' && goo[i][j] == 'W') {
				for (int k = i - 2; k <= i; ++k) {
					if (a[k][j] != -1) {
						int u = c, v = a[k][j];
						dbg (v);
						dbg (u);
						g[v].pb (sz (edges));
						edges.pb ({u, 0, 1});
						g[u].pb (sz (edges));
						edges.pb ({v, 0, 0});
					}
				}
				++c;
			}
		}
	}
	int st = c, fin = st + 1;
	dbg ("first");
	for (int i = 0; i < last; ++i) {
		dbg (i);
		g[st].pb (sz (edges));
		edges.pb ({i, 0, 1});
		g[i].pb (sz (edges));
		edges.pb ({st, 0, 0});
	}
	dbg ("second");
	for (int i = last; i < c; ++i) {
		dbg (i);
		g[i].pb (sz (edges));
		edges.pb ({fin, 0, 1});
		g[fin].pb (sz (edges));
		edges.pb ({i, 0, 0});
	}
	while (bfs (st, fin)) {
		while (dfs (st, fin));
		for (int i = 0; i <= fin; ++i) it[i] = 0;
	}
	int res = 0;
	for (auto& x: g[st]) {
		res += edges[x].f;
	}
	dbg (res);
	cout << c - res << '\n';








}

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 0 / 67