Submission #339483

#	Time	Username	Problem	Language	Result	Execution time	Memory
339483		bigDuck	Rice Hub (IOI11_ricehub)	C++14	100 / 100	25 ms	3124 KiB

ricehub

#include "ricehub.h"

#include<bits/stdc++.h>
using namespace std;
#define INIT  ios_base :: sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define mp make_pair
#define pb push_back
#define ft first
#define sc second
#define ll long long
#define pii pair<int, int>
#define count_bits __builtin_popcount
#define int ll

int d1[100010], d2[100010];
int x[100010], n;

int sum1(int i, int j){
    return d1[j]-d1[i]-(i)*(x[j]-x[i]);
}

int sum2(int i, int j){
    return d2[i]-d2[j]-(n-j-1)*(x[j]-x[i]);
}




int32_t besthub(int32_t R, int32_t L, int32_t X[], long long B)
{
    n=R;
    for(int i=0; i<R; i++){
        x[i]=X[i];

        if(i>0){
            d1[i]=d1[i-1]+(i)*(x[i]-x[i-1]);

        }

    }

    for(int i=R-1; i>=0; i--){

        if(i<(R-1)){
            d2[i]=d2[i+1]+(n-(i+1))*(x[i+1]-x[i]);

        }

    }

    int res=1;
    for(int i=0; i<R; i++){
        int l=0, r=R+1, m=(l+r)>>1ll;
        while(l<r){
            m=(l+r)>>1ll;
            int lt=0, rt=0;
            if( (m%2)==1){
                lt=m>>1ll; rt=m>>1ll;
            }
            else{
                rt=m>>1ll; lt=(m>>1ll)-1;
            }

            if( (lt>(i)) || (rt>(R-(i+1))) ){
                r=m; continue;
            }

            int sum=sum1(i-lt, i)+sum2(i, i+rt);

            if(sum>B){
                r=m;
            }
            else{
                l=(m+1);
            }
            m=(l+r)>>1ll;
        }
                int lt=0, rt=0;
            if( (m%2)==1){
                lt=m>>1ll; rt=m>>1ll;
            }
            else{
                rt=m>>1ll; lt=(m>>1ll)-1;
            }
        int sum=sum1(max(i-lt, 0ll), i)+sum2(i, i+rt);
        if( (sum>B) || (lt>(i)) || (rt>(R-(i+1))) ){
            m--;
        }
        res=max(res, m);

    }
    return res;
}

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