Submission #686334

#	Time	Username	Problem	Language	Result	Execution time	Memory
686334		Alihan_8	Table Tennis (info1cup20_tabletennis)	C++17	100 / 100	140 ms	5580 KiB

tabletennis

#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, k; cin >> n >> k;
    vector <int> p(n+k);
    for ( auto &i: p ) cin >> i;
    sort(all(p));
    vector <int> res(n);
    auto ok = [&](int sum){
        int l = 0, r = n+k-1, it = 0;
        while ( it < n and l < r and (r-l+1)+it >= n ){
            if ( p[l]+p[r] == sum ){
                res[it++] = p[l];
                res[it++] = p[r];
                l++, r--;
            }
            else if ( p[l]+p[r] < sum ) l++;
            else r--;
        }
        return it == n;
    };
    for ( int i = 0; i <= k; i++ ){
        for ( int j = n-1; j < n+k; j++ ){
            if ( ok(p[i]+p[j]) ){
                sort(all(res));
                for ( auto i: res ) cout << i << ' ';
                return 0;
            }
        }
    }
    assert(false);

    cout << '\n';
}

Compilation message (stderr)

tabletennis.cpp: In function 'void IO(std::string)':
tabletennis.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);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tabletennis.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: 11 / 11
• Subtask 2: 9 / 9
• Subtask 3: 14 / 14
• Subtask 4: 15 / 15
• Subtask 5: 9 / 9
• Subtask 6: 14 / 14
• Subtask 7: 15 / 15
• Subtask 8: 13 / 13