Submission #258948

#	Time	Username	Problem	Language	Result	Execution time	Memory
258948		Vimmer	Domino (COCI15_domino)	C++14	160 / 160	3877 ms	268628 KiB

domino

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
//
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("-O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("fast-math")
//#pragma GCC optimize("no-stack-protector")

#define F first
#define S second
#define sz(x) int(x.size())
#define pb push_back
#define pf push_front
#define N 100050
#define M ll(1e9 + 7)
#define inf 1e9 + 1e9

using namespace std;
using namespace __gnu_pbds;

typedef long double ld;
typedef long long ll;
typedef unsigned long long ull;
typedef short int si;
typedef array <ll, 5> a5;
typedef array <ll, 4> a4;

//typedef tree <ll, null_type, less_equal<ll>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;


gp_hash_table <int, gp_hash_table <int, int> > mp;

si a[2001][2001];

char mk[2001][2001];

int id = 2;

ll sum;

int ans, dp[500], pr[500];

vector <a5> edges;

bool cmp(a4 x, a4 y) {return a[x[0]][x[1]] + a[x[2]][x[3]] > a[y[0]][y[1]] + a[y[2]][y[3]];}

vector <a4 > gr;

vector <pair <int, int> > wh, bl;

bool opr(int &x, int &y) {return ((x + y) % 2) == 0;}

void add(pair <int, int> t) {if (mk[t.F][t.S] == 'b') return; mk[t.F][t.S] = 'b'; if (opr(t.F, t.S)) bl.pb({t.F, t.S}); else wh.pb({t.F, t.S});}

void add_edge(int from, int to, int cost)
{
    edges.pb({from, to, cost, 0, 1});

    edges.pb({to, from, -cost, 0, 0});
}

int main()
{
    //freopen("input.txt", "r", stdin); //freopen("output4.txt", "w", stdout);

    ios_base::sync_with_stdio(0); istream::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int n, k;

    cin >> n >> k;

    for (register int i = 0; i < n; i++)
      for (register int j = 0; j < n; j++)
      {
          cin >> a[i][j];

          sum += ll(a[i][j]);

          if (i != 0) gr.pb({i, j, i - 1, j});

          if (j != 0) gr.pb({i, j, i, j - 1});
      }

    sort(gr.begin(), gr.end(), cmp);

    for (int i = 0; i < min(50, sz(gr)); i++)
    {
        add({gr[i][0], gr[i][1]}); add({gr[i][2], gr[i][3]});

        pair <int, int> pt; pt.F = gr[i][0]; pt.S = gr[i][1];

        if (pt.F != 0) add({pt.F - 1, pt.S});

        if (pt.S != 0) add({pt.F, pt.S - 1});

        if (pt.F + 1 != n) add({pt.F + 1, pt.S});

        if (pt.S + 1 != n) add({pt.F, pt.S + 1});

        pt.F = gr[i][2]; pt.S = gr[i][3];

        if (pt.F != 0) add({pt.F - 1, pt.S});

        if (pt.S != 0) add({pt.F, pt.S - 1});

        if (pt.F + 1 != n) add({pt.F + 1, pt.S});

        if (pt.S + 1 != n) add({pt.F, pt.S + 1});
    }

    for (auto it : wh)
    {
        mp[it.F][it.S] = id++;

        add_edge(0, mp[it.F][it.S], 0);
    }

    for (auto it : bl)
    {
        mp[it.F][it.S] = id++;

        add_edge(mp[it.F][it.S], 1, 0);
    }

    for (auto it : wh)
    {
        if (it.F != 0 && mk[it.F - 1][it.S] == 'b') add_edge(mp[it.F][it.S], mp[it.F - 1][it.S], -(a[it.F][it.S] + a[it.F - 1][it.S]));

        if (it.S != 0 && mk[it.F][it.S - 1] == 'b') add_edge(mp[it.F][it.S], mp[it.F][it.S - 1], -(a[it.F][it.S] + a[it.F][it.S - 1]));

        if (it.F + 1 != n && mk[it.F + 1][it.S] == 'b') add_edge(mp[it.F][it.S], mp[it.F + 1][it.S], -(a[it.F][it.S] + a[it.F + 1][it.S]));

        if (it.S + 1 != n && mk[it.F][it.S + 1] == 'b') add_edge(mp[it.F][it.S], mp[it.F][it.S + 1], -(a[it.F][it.S] + a[it.F][it.S + 1]));
    }

    for (; k > 0; k--)
    {
        for (int i = 0; i < 500; i++) dp[i] = 2e9;

        dp[0] = 0;

        for (register int it = 0; it < 100; it++)
            for (register int i = 0; i < sz(edges); i++)
            {
                int to = edges[i][1], from = edges[i][0], cost = edges[i][2], flow = edges[i][3], cap = edges[i][4];

                if (flow < cap && dp[from] < 2e9 && dp[from] + cost < dp[to])
                {
                    dp[to] = dp[from] + cost;

                    pr[to] = i;
                }
            }

        ans += dp[1];

        int v = 1;

        while (v != 0)
        {
            int id = pr[v];

            edges[id][3]++;

            edges[id ^ 1][3]--;

            v = edges[id][0];
        }
    }

    cout << sum + ll(ans) << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10
• Subtask 11: 10 / 10
• Subtask 12: 10 / 10
• Subtask 13: 10 / 10
• Subtask 14: 10 / 10
• Subtask 15: 10 / 10
• Subtask 16: 10 / 10