Submission #1179958

#	Time	Username	Problem	Language	Result	Execution time	Memory
1179958		zadniprovska	T-Covering (eJOI19_covering)	C++20	0 / 100	116 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<ll> > a, vis;
ll x[17], y[17];

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

    if (type == 0) {
        if (x == n || y == 1 || y == m ||
            vis[x][y] || vis[x][y-1] || vis[x][y+1] || vis[x+1][y]) ans = -INF;

        else {
            vis[x][y] = vis[x][y-1] = vis[x][y+1] = vis[x+1][y] = 1;
            ans += a[x][y] + a[x][y-1] + a[x][y+1] + a[x+1][y];
        }
    }
    else if (type == 1) {
        if (x == 1 || y == 1 || y == m ||
            vis[x][y] || vis[x-1][y] || vis[x][y-1] || vis[x][y+1]) ans = -INF;

        else {
            vis[x][y] = vis[x-1][y] = vis[x][y-1] = vis[x][y+1] = 1;
            ans += a[x][y] + a[x-1][y] + a[x][y-1] + a[x][y+1];
        }
    }
    else if (type == 2) {
        if (x == 1 || x == n || y == m ||
            vis[x][y] || vis[x-1][y] || vis[x+1][y] || vis[x][y+1]) ans = -INF;

        else {
            vis[x][y] = vis[x-1][y] = vis[x+1][y] = vis[x][y+1] = 1;
            ans += a[x][y] + a[x-1][y] + a[x+1][y] + a[x][y+1];
        }
    }
    else {
        if (x == 1 || x == n || y == 1 ||
            vis[x][y] || vis[x-1][y] || vis[x+1][y] || vis[x][y-1]) ans = -INF;

        else {
            vis[x][y] = vis[x-1][y] = vis[x+1][y] = vis[x][y-1] = 1;
            ans += a[x][y] + a[x-1][y] + a[x+1][y] + a[x][y-1];
        }
    }

}

void solve() {

    ll n, m;
    cin >> n >> m;

    a.resize(n+1, vector<ll>(m+1));
    for (int i=1; i<=n; i++) {
        for (int j=1; j<=m; j++) {
            cin >> a[i][j];
        }
    }

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

        x[i]++; y[i]++;
    }


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

        ll rmask = mask;
        ans = 0;

        for (int i=1; i<=k; i++) {
            ll type = mask%2 + (mask/2) % 2;
            mask >>= 2;



            check(x[i], y[i], type);
            if (ans < 0) break;


        }

        for (int i=1; i<=k; i++) {
            vis[x[i]][y[i]] = vis[x[i]-1][y[i]] = vis[x[i]-1][y[i]-1] = vis[x[i]][y[i]-1] =
            vis[min(n, x[i]+1)][y[i]-1] = vis[min(n, x[i]+1)][y[i]] = vis[min(n, x[i]+1)][min(m, y[i]+1)] =
            vis[x[i]][min(m, y[i]+1)] = vis[x[i]-1][min(m, y[i]+1)] = 0;

        }

        mask = rmask;

        if (ans != -INF) ex = 1;
        answer = max(answer, ans);

    }

    if (!ex) 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;

}
;

Compilation message (stderr)

covering.cpp: In function 'long long int check(long long int, long long int, long long int)':
covering.cpp:65:1: warning: no return statement in function returning non-void [-Wreturn-type]
   65 | }
      | ^

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