Submission #1181485

#	Time	Username	Problem	Language	Result	Execution time	Memory
1181485		zadniprovska	T-Covering (eJOI19_covering)	C++20	15 / 100	1095 ms	167936 KiB

covering

#include <bits/stdc++.h>

using namespace std;

#define el '\n'
#define ll long long
#define ld long double
#define ull unsigned long long
#define pll pair<long long, long long>
#define ppll pair< pair<long long, long long>, long long >
#define ff first
#define ss second
#define pb push_back
#define pf push_front
#define all(x) x.begin(), x.end()

const ll DIM = 2e5 + 7;
const ll INF = 1e18;
const ll mod = 1e9 + 7;
const ll maxlog = 20;

ll n, m, ans;
vector< vector<int> > a;
vector< vector<bool> > vis;
int x[17], y[17];

const vector<vector<pll>> d = {
    {{0, 0}, {0, -1}, {0, 1}, {1, 0}},
    {{0, 0}, {0, -1}, {0, 1}, {-1, 0}},
    {{0, 0}, {-1, 0}, {1, 0}, {0, 1}},
    {{0, 0}, {-1, 0}, {1, 0}, {0, -1}}
};

ll check(ll x, ll y, ll type) {

    ll res = 0;
    for (auto [dx, dy] : d[type]) {
        ll nx = x+dx, ny = y+dy;
        if (nx < 0 || nx >= n || ny < 0 || ny >= m || vis[nx][ny]) return -1;

        vis[nx][ny] = 1;


        res += a[nx][ny];
    }
    return res;

}

void solve() {

    cin >> n >> m;

    a.resize(n, vector<int>(m));
    for (int i=0; i<n; i++) {
        for (int j=0; j<m; j++) {
            cin >> a[i][j];
        }
    }

    int k;
    cin >> k;
    for (int i=1; i<=k; i++) {
        cin >> x[i] >> y[i];
    }


    ll answer = -INF;
    vis.resize(n, vector<bool>(m, 0));
    for (int mask = 0; mask < (1 << (2*k)); mask++) {

        ll rmask = mask;
        ans = 0;
        int ex = 1;

        vis.assign(n, vector<bool>(m, false));
        for (int i=1; i<=k; i++) {
            ll type = (rmask%2)*2 + (rmask/2) % 2;
            rmask >>= 2;



            ll cur = check(x[i], y[i], type);
            if (cur == -1) {
                ex = 0;
                break;
            }

            ans += cur;


        }


        if (ex) answer = max(answer, ans);

    }

    if (answer == -INF) cout << "No" << el;
    else cout << answer << el;

}



signed main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
    //freopen("nocross.in", "r", stdin);
    //freopen("nocross.out", "w", stdout);

    int ntest = 1;
    //cin >> ntest;
    while (ntest--){
        solve();
    }
    return 0;

}
;

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 15 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 30