Submission #339912

#	Time	Username	Problem	Language	Result	Execution time	Memory
339912		Sho10	Rice Hub (IOI11_ricehub)	C++14	0 / 100	6 ms	1132 KiB

ricehub

#include <bits/stdc++.h> //Andrei Alexandru a.k.a Sho10
#include "ricehub.h"
#define ll long long
#define double long double
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#define all(a) (a).begin(), (a).end()
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define pi pair
#define rc(s) return cout<<s,0
#define endl '\n'
#define mod 1000000007
#define PI 3.14159265359
#define MAXN 100005
#define INF 1000000005
#define LINF 1000000000000000005ll
#define CODE_START  ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
ll n,pref[200005],suf[200005],a[200005];
ll calc1(ll i,ll j){
return pref[j]-pref[i]-i*(a[j]-a[i]);
}
ll calc2(ll i,ll j){
    return suf[i]-suf[j]-(n-j-1)*(a[j]-a[i]);
}
int32_t besthub(int32_t R,int32_t L,int32_t X[],ll B){
    n=R;
    for(ll i=0;i<n;i++)
    {
        a[i]=X[i];
        if(i>0){
            pref[i]=pref[i-1]+i*(a[i]-a[i-1]);
        }
    }
    for(ll i=n-1;i>=0;i--)
    {
        if(i<n-1){
            suf[i]=suf[i+1]+(n-i-1)*(a[i+1]-a[i]);
        }
    }
    ll ans=1;
    for(ll i=0;i<n;i++){
        ll l=0,r=n+1,mid;
        while(l<r){
            ll mid=(l+r)/2,x=0,y=0;
            if(mid%2==1){
                x=mid/2;
                y=mid/2;
            }else {
            y=mid/2;
            x=mid/2-1;
            }
            if(x>i||y>(n-i-1)){
                r=mid;
                continue;
            }

            ll sum=calc1(i-x,i)+calc2(i,i+y);
            if(sum>B){
                r=mid;
            }else {
            l=mid+1;
            }
            mid=(l+r)/2;
        }
        ll x=0,y=0;
          if(mid%2==1){
                x=mid/2;
                y=mid/2;
            }else {
            y=mid/2;
            x=mid/2-1;
            }
            ll sum=calc1(max(0ll,i-x),i)+calc2(i,i+y);
            if(sum>B||x>i||y>(n-i-1)){
                mid--;
            }
            ans=max(ans,mid);

    }
    return ans;
}
/*
int32_t main(){
CODE_START;
*/

Compilation message (stderr)

ricehub.cpp: In function 'int32_t besthub(int32_t, int32_t, int32_t*, long long int)':
ricehub.cpp:70:17: warning: 'mid' may be used uninitialized in this function [-Wmaybe-uninitialized]
   70 |           if(mid%2==1){
      |              ~~~^~

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