Submission #306002

#	Time	Username	Problem	Language	Result	Execution time	Memory
306002		vipghn2003	Rice Hub (IOI11_ricehub)	C++14	100 / 100	114 ms	2948 KiB

ricehub

#include<bits/stdc++.h>

using namespace std;

const int N=1e5+5;
int a[N];
long long s[N];

long long cost(int i,int l,int r)
{
    if(l>r) return 0;
    return 1ll*a[i]*(i-l)-(s[i-1]-s[l-1])+(s[r]-s[i])-1ll*a[i]*(r-i);
}

int besthub(int R,int L,int X[],long long B)
{
    for(int i=1;i<=R;i++)
    {
        a[i]=X[i-1];
        s[i]=s[i-1]+a[i];
    }
    int ans=0;
    for(int i=1;i<=R;i++)
    {
        int pos=a[i];
        int l=i,r=R,res=-1;
        while(l<=r)
        {
            int mid=(l+r)/2;
            int v=mid;
            int need=pos-(a[mid]-pos);
            int u=upper_bound(a+1,a+R+1,need)-a;
            if(cost(i,u,v)<=B)
            {
                res=mid;
                l=mid+1;
            }
            else r=mid-1;
        }
        int need=pos-(a[res]-pos);
        int u=upper_bound(a+1,a+R+1,need)-a;
        long long cur=B-cost(i,u,res);
        l=1,r=u;
        int id;
        while(l<=r)
        {
            int mid=(l+r)/2;
            if(1ll*pos*(u-mid)-(s[u-1]-s[mid-1])>cur) l=mid+1;
            else
            {
                id=mid;
                r=mid-1;
            }
        }
        ans=max(ans,res-id+1);
    }
    return ans;
}
/*
int main()
{
    int R,L,B;
    cin>>R>>L>>B;
    int pos[R];
    for(int i=0;i<R;i++) cin>>pos[i];
    cout<<besthub(R,L,pos,B);
}
5 20 6
1
2
10
12
14
*/

Compilation message (stderr)

ricehub.cpp: In function 'int besthub(int, int, int*, long long int)':
ricehub.cpp:55:24: warning: 'id' may be used uninitialized in this function [-Wmaybe-uninitialized]
   55 |         ans=max(ans,res-id+1);
      |                     ~~~^~~

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