Submission #463928

#	Time	Username	Problem	Language	Result	Execution time	Memory
463928		NhatMinh0208	Dango Maker (JOI18_dango_maker)	C++17	33 / 100	423 ms	262148 KiB

dango_maker

#ifndef CPL_TEMPLATE
#define CPL_TEMPLATE
/*
	Normie's Template v2.5
	Changes:
    Added warning against using pragmas on USACO.
*/
// Standard library in one include.
#include <bits/stdc++.h>
using namespace std;
 
// ordered_set library.
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set(el) tree<el,null_type,less<el>,rb_tree_tag,tree_order_statistics_node_update>
 
// AtCoder library. (Comment out these two lines if you're not submitting in AtCoder.) (Or if you want to use it in other judges, run expander.py first.)

#include <algorithm>
#include <cassert>
#include <limits>
#include <queue>
#include <vector>


#include <vector>

namespace atcoder {

namespace internal {

template <class T> struct simple_queue {
    std::vector<T> payload;
    int pos = 0;
    void reserve(int n) { payload.reserve(n); }
    int size() const { return int(payload.size()) - pos; }
    bool empty() const { return pos == int(payload.size()); }
    void push(const T& t) { payload.push_back(t); }
    T& front() { return payload[pos]; }
    void clear() {
        payload.clear();
        pos = 0;
    }
    void pop() { pos++; }
};

}  // namespace internal

}  // namespace atcoder


namespace atcoder {

template <class Cap> struct mf_graph {
  public:
    mf_graph() : _n(0) {}
    explicit mf_graph(int n) : _n(n), g(n) {}

    int add_edge(int from, int to, Cap cap) {
        assert(0 <= from && from < _n);
        assert(0 <= to && to < _n);
        assert(0 <= cap);
        int m = int(pos.size());
        pos.push_back({from, int(g[from].size())});
        int from_id = int(g[from].size());
        int to_id = int(g[to].size());
        if (from == to) to_id++;
        g[from].push_back(_edge{to, to_id, cap});
        g[to].push_back(_edge{from, from_id, 0});
        return m;
    }

    struct edge {
        int from, to;
        Cap cap, flow;
    };

    edge get_edge(int i) {
        int m = int(pos.size());
        assert(0 <= i && i < m);
        auto _e = g[pos[i].first][pos[i].second];
        auto _re = g[_e.to][_e.rev];
        return edge{pos[i].first, _e.to, _e.cap + _re.cap, _re.cap};
    }
    std::vector<edge> edges() {
        int m = int(pos.size());
        std::vector<edge> result;
        for (int i = 0; i < m; i++) {
            result.push_back(get_edge(i));
        }
        return result;
    }
    void change_edge(int i, Cap new_cap, Cap new_flow) {
        int m = int(pos.size());
        assert(0 <= i && i < m);
        assert(0 <= new_flow && new_flow <= new_cap);
        auto& _e = g[pos[i].first][pos[i].second];
        auto& _re = g[_e.to][_e.rev];
        _e.cap = new_cap - new_flow;
        _re.cap = new_flow;
    }

    Cap flow(int s, int t) {
        return flow(s, t, std::numeric_limits<Cap>::max());
    }
    Cap flow(int s, int t, Cap flow_limit) {
        assert(0 <= s && s < _n);
        assert(0 <= t && t < _n);
        assert(s != t);

        std::vector<int> level(_n), iter(_n);
        internal::simple_queue<int> que;

        auto bfs = [&]() {
            std::fill(level.begin(), level.end(), -1);
            level[s] = 0;
            que.clear();
            que.push(s);
            while (!que.empty()) {
                int v = que.front();
                que.pop();
                for (auto e : g[v]) {
                    if (e.cap == 0 || level[e.to] >= 0) continue;
                    level[e.to] = level[v] + 1;
                    if (e.to == t) return;
                    que.push(e.to);
                }
            }
        };
        auto dfs = [&](auto self, int v, Cap up) {
            if (v == s) return up;
            Cap res = 0;
            int level_v = level[v];
            for (int& i = iter[v]; i < int(g[v].size()); i++) {
                _edge& e = g[v][i];
                if (level_v <= level[e.to] || g[e.to][e.rev].cap == 0) continue;
                Cap d =
                    self(self, e.to, std::min(up - res, g[e.to][e.rev].cap));
                if (d <= 0) continue;
                g[v][i].cap += d;
                g[e.to][e.rev].cap -= d;
                res += d;
                if (res == up) return res;
            }
            level[v] = _n;
            return res;
        };

        Cap flow = 0;
        while (flow < flow_limit) {
            bfs();
            if (level[t] == -1) break;
            std::fill(iter.begin(), iter.end(), 0);
            Cap f = dfs(dfs, t, flow_limit - flow);
            if (!f) break;
            flow += f;
        }
        return flow;
    }

    std::vector<bool> min_cut(int s) {
        std::vector<bool> visited(_n);
        internal::simple_queue<int> que;
        que.push(s);
        while (!que.empty()) {
            int p = que.front();
            que.pop();
            visited[p] = true;
            for (auto e : g[p]) {
                if (e.cap && !visited[e.to]) {
                    visited[e.to] = true;
                    que.push(e.to);
                }
            }
        }
        return visited;
    }

  private:
    int _n;
    struct _edge {
        int to, rev;
        Cap cap;
    };
    std::vector<std::pair<int, int>> pos;
    std::vector<std::vector<_edge>> g;
};

}  // namespace atcoder

using namespace atcoder;

//Pragmas (Comment out these three lines if you're submitting in szkopul or USACO.)
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast,unroll-loops,tree-vectorize")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
 
//File I/O.
#define FILE_IN "cseq.inp"
#define FILE_OUT "cseq.out"
#define ofile freopen(FILE_IN,"r",stdin);freopen(FILE_OUT,"w",stdout)
 
//Fast I/O.
#define fio ios::sync_with_stdio(0);cin.tie(0)
#define nfio cin.tie(0)
#define endl "\n"
 
//Order checking.
#define ord(a,b,c) ((a>=b)and(b>=c))
 
//min/max redefines, so i dont have to resolve annoying compile errors.
#define min(a,b) (((a)<(b))?(a):(b))
#define max(a,b) (((a)>(b))?(a):(b))

// Fast min/max assigns to use with AVX.
// Requires g++ 9.2.0.
template<typename T>
__attribute__((always_inline)) void chkmin(T& a, const T& b) {
    a=(a<b)?a:b;
}

template<typename T>
__attribute__((always_inline)) void chkmax(T& a, const T& b) {
    a=(a>b)?a:b;
}
 
//Constants.
#define MOD (ll(998244353))
#define MAX 300001
#define mag 320
const long double PI=3.14159265358979;
 
//Pairs and 3-pairs.
#define p1 first
#define p2 second.first
#define p3 second.second
#define fi first
#define se second
#define pii(element_type) pair<element_type,element_type>
#define piii(element_type) pair<element_type,pii(element_type)>
 
//Quick power of 2.
#define pow2(x) (ll(1)<<x)
 
//Short for-loops.
#define ff(i,__,___) for(int i=__;i<=___;i++)
#define rr(i,__,___) for(int i=__;i>=___;i--)
 
//Typedefs.
#define bi BigInt
typedef long long ll;
typedef long double ld;
typedef short sh;

// Binpow and stuff
ll BOW(ll a, ll x, ll p)
{
	if (!x) return 1;
	ll res=BOW(a,x/2,p);
	res*=res;
	res%=p;
	if (x%2) res*=a;
	return res%p;
}
ll INV(ll a, ll p)
{
	return BOW(a,p-2,p);
}
//---------END-------//
#endif
vector<int> vec;
int n,m,i,j,k,t,t1,u,v,a,b;
int arr[3001][3001];
vector<int> lmao[3001][3001];

int main()
{
	fio;
    cin>>n>>m;
    char c;
    for (i=1;i<=n;i++) for (j=1;j<=m;j++)
    {
        cin>>c;
        if (c=='R') arr[i][j]=0;
        else if (c=='G') arr[i][j]=1;
        else arr[i][j]=2;
    }
    t=0;
    for (i=1;i<=n;i++) for (j=1;j<=m-2;j++)
    {
        if (arr[i][j]==0 && arr[i][j+1]==1 && arr[i][j+2]==2) 
        {
            t++;
            lmao[i][j].push_back(t);
            lmao[i][j+1].push_back(t);
            lmao[i][j+2].push_back(t);
        }
    }
    t1=t;
    for (i=1;i<=n-2;i++) for (j=1;j<=m;j++)
    {
        if (arr[i][j]==0 && arr[i+1][j]==1 && arr[i+2][j]==2) 
        {
            t++;
            lmao[i][j].push_back(t);
            lmao[i+1][j].push_back(t);
            lmao[i+2][j].push_back(t);
        }
    }
    mf_graph<int> gr(t+2);
    for (i=1;i<=t1;i++) gr.add_edge(0,i,1);
    for (i=t1+1;i<=t;i++) gr.add_edge(i,t+1,1);
    for (i=1;i<=n;i++) for (j=1;j<=m;j++) if (lmao[i][j].size()==2)
    {
        gr.add_edge(lmao[i][j][0],lmao[i][j][1],1);
    }
    cout<<t-gr.flow(0,t+1);
}
// Normie28

Compilation message (stderr)

dango_maker.cpp:195: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
  195 | #pragma comment(linker, "/stack:200000000")
      |

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