Submission #456340

#	Time	Username	Problem	Language	Result	Execution time	Memory
456340		SamAnd	T-Covering (eJOI19_covering)	C++17	100 / 100	260 ms	26468 KiB

covering

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 1000006;
const int xx[4] = {0, 1, 0, -1};
const int yy[4] = {1, 0, -1, 0};
//const int cc[4] = {'R', 'D', 'L', 'U'};

int n, m;

template <typename T>
void bil(T**& a)
{
    a = new T*[n + 5];
    for (int i = 0; i < n + 5; ++i)
        a[i] = new T[m + 5];
    for (int i = 0; i <= n + 1; ++i)
    {
        for (int j = 0; j <= m + 1; ++j)
        {
            a[i][j] = 0;
        }
    }
}

int** a;

int k;
bool** c;

bool** cc;
vector<pair<int, int> > v;
void dfs(int x, int y)
{
    cc[x][y] = true;
    v.push_back(m_p(x, y));
    for (int i = 0; i < 4; ++i)
    {
        int hx = x + xx[i] * 2;
        int hy = y + yy[i] * 2;
        if (1 <= hx && hx <= n && 1 <= hy && hy <= m)
        {
            if (c[hx][hy] && !cc[hx][hy])
            {
                dfs(hx, hy);
            }
        }
    }
}

void solv()
{
    cin >> n >> m;
    bil(a);
    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            cin >> a[i][j];
        }
    }

    cin >> k;
    bil(c);
    for (int i = 0; i < k; ++i)
    {
        int x, y;
        cin >> x >> y;
        ++x;
        ++y;
        c[x][y] = true;
    }

    int** u;
    bil(u);
    for (int i = 0; i <= n + 1; ++i)
    {
        for (int j = 0; j <= m + 1; ++j)
        {
            u[i][j] = -1;
        }
    }

    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            if (c[i][j] && c[i][j + 1])
            {
                u[i][j] = 2;
                u[i][j + 1] = 0;
            }
            if (c[i][j] && c[i + 1][j])
            {
                u[i][j] = 3;
                u[i + 1][j] = 1;
            }
            if (c[i][j] && c[i + 1][j + 1])
            {
                u[i][j] = 2;
                u[i + 1][j + 1] = 0;
            }
            if (c[i][j] && c[i - 1][j + 1])
            {
                u[i][j] = 2;
                u[i - 1][j + 1] = 0;
            }
        }
    }

    int** q;
    bil(q);
    for (int j = 0; j <= m; ++j)
    {
        q[0][j] = q[n + 1][j] = 1;
    }
    for (int i = 0; i <= n; ++i)
    {
        q[i][0] = q[i][m + 1] = 1;
    }
    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            if (u[i][j] != -1)
            {
                c[i][j] = false;
                ++q[i][j];
                for (int d = -1; d <= 1; ++d)
                    ++q[i + xx[(u[i][j] + d + 4) % 4]][j + yy[(u[i][j] + d + 4) % 4]];
            }
        }
    }

    for (int i = 0; i <= n + 1; ++i)
    {
        for (int j = 0; j <= m + 1; ++j)
        {
            if (q[i][j] > 1)
            {
                cout << "No\n";
                return;
            }
        }
    }

    int ans = 0;

    bil(cc);
    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            if (c[i][j] && !cc[i][j])
            {
                v.clear();
                dfs(i, j);
                set<pair<int, int> > s;
                for (int i = 0; i < sz(v); ++i)
                {
                    ++q[v[i].fi][v[i].se];
                    for (int j = 0; j < 4; ++j)
                    {
                        if (!q[v[i].fi + xx[j]][v[i].se + yy[j]])
                            s.insert(m_p(v[i].fi + xx[j], v[i].se + yy[j]));
                    }
                }
                if (sz(s) < sz(v) * 3)
                {
                    cout << "No\n";
                    return;
                }
                if (sz(s) == sz(v) * 3)
                {
                    for (auto it = s.begin(); it != s.end(); ++it)
                        ans += a[it->fi][it->se];
                }
                else
                {
                    int minu = N;
                    for (auto it = s.begin(); it != s.end(); ++it)
                    {
                        ans += a[it->fi][it->se];
                        minu = min(minu, a[it->fi][it->se]);
                    }
                    ans -= minu;
                }
            }
        }
    }

    for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            if (q[i][j])
                ans += a[i][j];
        }
    }

    cout << ans << "\n";
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    ios_base::sync_with_stdio(false), cin.tie(0);

    int tt = 1;
    //cin >> tt;
    while (tt--)
    {
        solv();
    }
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 15 / 15
• Subtask 6: 20 / 20
• Subtask 7: 30 / 30