Submission #705927

#	Time	Username	Problem	Language	Result	Execution time	Memory
705927		Alihan_8	Rice Hub (IOI11_ricehub)	C++17	43 / 100	69 ms	2384 KiB

ricehub

#include <bits/stdc++.h>
#include "ricehub.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
typedef long long ll;
int besthub(int R, int L, int X[], ll B){
    int n = R;
    vector <int> p;
    for ( int i = 0; i < n; i++ ) p.pb(X[i]);
    sort(all(p));
    auto f = [&](int pos){
        int l = -1, r = n;
        for ( int i = 0; i < n; i++ ){
            if ( p[i] <= pos ) l = i;
            else r = min(r, i);
        }
        auto F = [&](int it){
            return abs(p[it]-pos);
        };
        ll sum = 0;
        int cnt = 0;
        while ( true ){
            if ( l == -1 ){
                if ( r == n or sum+F(r) > B ) break;
                sum += F(r++);
                cnt++;
            }
            else{
                if ( r == n ){
                    if ( sum+F(l) > B ) break;
                    sum += F(l--); cnt++;
                }
                else{
                    int Mn = min(F(l), F(r));
                    if ( sum+Mn > B ) break;
                    sum += Mn; cnt++;
                    if ( Mn == F(l) ) l--;
                    else r++;
                }
            }
        }
        return cnt;
    };
    int l = 0, r = 1e9;
    for ( int _ = 1; _ <= 100; _++ ){
        int m1 = l+(r-l)/3;
        int m2 = r-(r-l)/3;
        if ( f(m1) >= f(m2) ) r = m2;
        else l = m1;
    }
    int Mx = 0;
    for ( int i = l; i <= r; i++ ){
        Mx = max(Mx, f(i));
    }
    return Mx;
}
#if false
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int R, L, B;
    cin >> R >> L >> B;
    int X[R];
    for ( int i = 0; i < R; i++ ) cin >> X[i];
    cout << besthub(R, L, X, B);

    cout << '\n';
/*
5 20 6
1 2 10 12 14
answer: 3
*/
}
#endif

Compilation message (stderr)

ricehub.cpp: In function 'void IO(std::string)':
ricehub.cpp:12:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ricehub.cpp:12:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 17 / 17
• Subtask 2: 0 / 25
• Subtask 3: 26 / 26
• Subtask 4: 0 / 32