Submission #916250

#	Time	Username	Problem	Language	Result	Execution time	Memory
916250		JakobZorz	Dancing Elephants (IOI11_elephants)	C++17	26 / 100	509 ms	20244 KiB

elephants

#include"elephants.h"
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
typedef long long ll;

const int BUCKET_SIZE=256;
ll n,l;
ll pos[150000];

struct Bucket{
    vector<ll>arr;
    vector<ll>num;
    vector<ll>pos;
    
    void regen(){
        num.resize(arr.size());
        pos.resize(arr.size());
        for(int i=(int)arr.size()-1;i>=0;i--){
            num[i]=1;
            ll p=arr[i]+l;
            if(p>=arr.back()){
                pos[i]=p;
                continue;
            }
            
            int l=i-1,r=(int)arr.size()-1;
            while(l<r-1){
                int m=(l+r)/2;
                if(arr[m]<=p)
                    l=m;
                else
                    r=m;
            }
            num[i]=num[r]+1;
            pos[i]=pos[r];
        }
    }
    
    void erase(int el){
        auto it=lower_bound(arr.begin(),arr.end(),el);
        arr.erase(it);
        
        regen();
    }
    
    void add(int el){
        auto it=upper_bound(arr.begin(),arr.end(),el);
        arr.insert(it,el);
        
        regen();
    }
    
    pair<ll,ll>get(ll p){
        if(arr.empty()||p>=arr.back())
            return{0,p};
        
        int l=-1,r=(int)arr.size()-1;
        while(l<r-1){
            int m=(l+r)/2;
            if(arr[m]<=p)
                l=m;
            else
                r=m;
        }
        
        return{num[r],pos[r]};
    }
};

vector<Bucket*>buckets;

void init(int N,int L,int X[]){
    n=N;
    l=L;
    vector<int>vec;
    for(int i=0;i<n;i++){
        pos[i]=X[i];
        vec.push_back(X[i]);
    }
    sort(vec.begin(),vec.end());
    buckets.push_back(new Bucket);
    for(int i:vec){
        buckets.back()->arr.push_back(i);
        if((int)buckets.back()->arr.size()>=BUCKET_SIZE){
            buckets.push_back(new Bucket);
        }
    }
    
    for(auto i:buckets)
        i->regen();
}

int update(int i,int y){
    // balance buckets
    for(int i=0;i<(int)buckets.size();i++){
        if(buckets[i]->arr.size()>=2*BUCKET_SIZE){
            buckets.insert(buckets.begin()+i+1,new Bucket);
            buckets[i+1]->arr={buckets[i]->arr.begin()+buckets[i]->arr.size()/2,buckets[i]->arr.end()};
            buckets[i]->arr.erase(buckets[i]->arr.begin()+buckets[i]->arr.size()/2,buckets[i]->arr.end());
            buckets[i]->regen();
            buckets[i+1]->regen();
        }
    }
    
    for(auto b:buckets){
        if(b->arr[0]<=pos[i]&&pos[i]<=b->arr.back()){
            b->erase(pos[i]);
            break;
        }
    }
    pos[i]=y;
    
    int cb=0;
    while(cb<(int)buckets.size()){
        if(!buckets[cb]->arr.empty()&&buckets[cb]->arr[0]>=y)
            break;
        cb++;
    }
    if(cb)
        cb--;
    
    buckets[cb]->add(y);
    
    ll pos=-1,res=0;
    
    for(auto b:buckets){
        auto r=b->get(pos);
        res+=r.first;
        pos=r.second;
    }
    
    return res;
}

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 47
• Subtask 5: 0 / 3