Submission #672983

#	Time	Username	Problem	Language	Result	Execution time	Memory
672983		Alihan_8	Luxury burrow (IZhO13_burrow)	C++17	100 / 100	682 ms	25676 KiB

burrow

#include <bits/stdc++.h>
// include <ext/pb_ds/assoc_container.hpp>
// include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;
using namespace std;
#define all(x) x.begin(), x.end()
#define pb push_back
// define ordered_set tree<int,null_type,less_equal<int>,rb_tree_tag,tree_order_statistics_node_update>
#define mpr make_pair
#define ln '\n'
void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
#define int long long
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n, m, k; cin >> n >> m >> k;
    vector <vector<int>> p(n);
    for ( auto &i: p ){
        i.resize(m);
        for ( auto &j: i ) cin >> j;
    }
    auto chmax = [&](int &l, int r){l = max(l, r);};
    auto calc = [&](vector <int> &x){
        auto f = [&](){
            stack <int> stk;
            vector <int> res(m);
            stk.push(-1);
            for ( int i = 0; i < m; i++ ){
                while ( stk.top() != -1 and x[stk.top()] >= x[i] ) stk.pop();
                res[i] = stk.top()+1;
                stk.push(i);
            }
            return res;
        };
        vector <int> l = f();
        reverse(all(x));
        vector <int> r = f();
        reverse(all(x));
        for ( int i = 0; i < m; i++ ) r[i] = m-1-r[i];
        reverse(all(r));
        int Mx = 0;
        for ( int i = 0; i < m; i++ ) chmax(Mx, (r[i]-l[i]+1)*x[i]);
        return Mx;
    };
    auto f = [&](int T){
        vector <vector<int>> bits(n, vector <int> (m));
        for ( int i = 0; i < n; i++ ){
            for ( int j = 0; j < m; j++ ){
                bits[i][j] = p[i][j] >= T;
            }
        }
        vector <int> x(m);
        int Mx = 0;
        for ( int i = 0; i < n; i++ ){
            for ( int j = 0; j < m; j++ ){
                if ( bits[i][j] ) x[j]++;
                else x[j] = 0;
            }
            chmax(Mx, calc(x));
        }
        return Mx;
    };
    int l = 1, r = 1e9+1;
    while ( l+1 < r ){
        int md = (l+r)>>1;
        if ( f(md) < k ) r = md;
        else l = md;
    }
    cout << l << ' ' << f(l);

    cout << '\n';
}

Compilation message (stderr)

burrow.cpp: In function 'void IO(std::string)':
burrow.cpp:11:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
burrow.cpp:11:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100