Submission #1003276

#	Time	Username	Problem	Language	Result	Execution time	Memory
1003276		vjudge1	Rice Hub (IOI11_ricehub)	C++17	68 / 100	9 ms	2652 KiB

ricehub

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define f first
#define s second
#define pf push_front
#define pb push_back
#define pi pair<int,int>
#define vi vector<int>

/*
int besthub(int n, int last, int x[], ll b){
    

    int ans = 0;
    int l , r;
    for(int i = 0; i < n; i++){
        
        l = i - (lower_bound(x.begin(), x.end(), max(0LL,x[i]-b))- x.begin());
        r =  upper_bound(x.begin(), x.end(), min((ll) last, x[i]+b)) - x.begin() - (i+1);
       // cout << x[i] << " " <<l << " " << r << endl;
        ans = max(l+r+1,ans);
    }
    
    return ans;

}

*/

int besthub(int n, int last, int x[], ll b){
    

    ll ans = 0;
    
    ll cnt;
    ll pref[n+1];
    pref[0] = 0;
    
    
 
    for(int i = 1; i <= n; i++){
        pref[i] = pref[i-1]+x[i-1];
    }
  /*  
    for(int i : pref){
        cout << i << " ";
    }
    cout << endl;
    */
    
    int l = 1;
    int final = 1;
    
    for(int r =1; r <= n;r++){
        int m = (l+r)/2;
       
     //   ll val = pref[r] - pref[m] + (pref[m]-pref[max(0,l)]);
       ll val= ((x[m-1]*(m-l)) - (pref[m-1]-pref[l-1]) + ((pref[r]-pref[m]) - (x[m-1]*(r-m))));
       //cout <<l << " "<< r << " " << val<<endl;
       
       
       // cout << val << endl;
        if( ((x[m-1]*(m-l)) - (pref[m-1]-pref[l-1]) + ((pref[r]-pref[m]) - (x[m-1]*(r-m))))<= b){
           // cout << l << " " << r << endl;
            final = max(final,r-l+1);
        }
        else{
            while(((x[m-1]*(m-l)) - (pref[m-1]-pref[l-1]) + ((pref[r]-pref[m]) - (x[m-1]*(r-m)))) > b && l<r){
                m = (l+r)/2;
                l++;
            }
            m = (l+r)/2;
            if(((x[m-1]*(m-l)) - (pref[m-1]-pref[l-1]) + ((pref[r]-pref[m]) - (x[m-1]*(r-m))))<= b){
                 final = max(final,r-l+1);
            }
            
        }
    }
    
    return final;

}

Compilation message (stderr)

ricehub.cpp: In function 'int besthub(int, int, int*, long long int)':
ricehub.cpp:59:11: warning: unused variable 'val' [-Wunused-variable]
   59 |        ll val= ((x[m-1]*(m-l)) - (pref[m-1]-pref[l-1]) + ((pref[r]-pref[m]) - (x[m-1]*(r-m))));
      |           ^~~
ricehub.cpp:34:8: warning: unused variable 'ans' [-Wunused-variable]
   34 |     ll ans = 0;
      |        ^~~
ricehub.cpp:36:8: warning: unused variable 'cnt' [-Wunused-variable]
   36 |     ll cnt;
      |        ^~~

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