Submission #707199

#	Time	Username	Problem	Language	Result	Execution time	Memory
707199		Alihan_8	Exhibition (JOI19_ho_t2)	C++17	100 / 100	69 ms	5580 KiB

joi2019_ho_t2

#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<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; cin >> n >> m;
    vector <pair<int,int>> p(n);
    for ( auto &[r, l]: p ) cin >> l >> r;
    vector <int> C(m);
    for ( auto &i: C ) cin >> i;
    sort(all(C)); sort(all(p));
    for ( auto &[l, r]: p ) swap(l, r);
    auto ok = [&](int X){
        int it = 0;
        for ( int i = m-X; i < m; i++ ){
            while ( it < n and p[it].first > C[i] ) it++;
            if ( it == n ) return false;
            it++;
        }
        return true;
    };
    int l = 0, r = min(m+1, n+1);
    while ( l+1 < r ){
        int md = (l+r) >> 1;
        if ( ok(md) ) l = md;
        else r = md;
    }
    cout << l;

    cout << '\n';
}

Compilation message (stderr)

joi2019_ho_t2.cpp: In function 'void IO(std::string)':
joi2019_ho_t2.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);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
joi2019_ho_t2.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: 10 / 10
• Subtask 2: 40 / 40
• Subtask 3: 50 / 50