Submission #1020579

#	Time	Username	Problem	Language	Result	Execution time	Memory
1020579		simona1230	Holiday (IOI14_holiday)	C++17	100 / 100	583 ms	11020 KiB

holiday

#include"holiday.h"
#include<bits/stdc++.h>
using namespace std;

long long a[100001],n,s,d;
long long tidx[100001],fl,fr;
pair<long long,long long> p[100001];
long long ans;

struct tree
{
    long long act,val;
    tree(){}

    tree(long long a,long long v)
    {
        act=a;
        val=v;
    }
};

tree t[400001];

void update(long long i,long long l,long long r,long long idx,long long tp)
{
    if(l==r)
    {
        //cout<<p[l].first<<" "<<tp<<endl;
        t[i].act=tp;
        if(t[i].act)t[i].val=p[l].first;
        else t[i].val=0;

        return;
    }

    long long m=(l+r)/2;
    if(idx<=m)update(i*2,l,m,idx,tp);
    else update(i*2+1,m+1,r,idx,tp);

    t[i].act=t[i*2].act+t[i*2+1].act;
    t[i].val=t[i*2].val+t[i*2+1].val;
}

long long query(long long i,long long l,long long r,long long x)
{
    if(t[i].act<=x)return t[i].val;
    long long m=(l+r)/2;

    if(t[i*2].act<x)
        return t[i*2].val+query(i*2+1,m+1,r,x-t[i*2].act);
    return query(i*2,l,m,x);
}


void change(long long l,long long r)
{
    //cout<<"c "<<fl<<" "<<fr<<" "<<l<<" "<<r<<endl;
    while(fl<l)
    {
        update(1,0,n-1,tidx[fl],0);
        fl++;
    }

    while(l<fl)
    {
        fl--;
        update(1,0,n-1,tidx[fl],1);
    }

    while(r<fr)
    {
        update(1,0,n-1,tidx[fr],0);
        fr--;
    }

    while(fr<r)
    {
        fr++;
        update(1,0,n-1,tidx[fr],1);
    }
}

void div(long long l,long long r,long long optl,long long optr)
{
    if(l>r)return;

    long long m=(l+r)/2;
    //cout<<m<<": "<<endl;
    long long maxx=-1,idxm=0,last=0;
    for(long long i=optl;i<=optr;i++)
    {
        change(i,m);
        long long days=d-2*(m-s)-(s-i),val;
        if(days<=0)val=0;
        else val=query(1,0,n-1,days);
        //cout<<i<<" "<<m<<" "<<days<<" "<<val<<endl;
        ans=max(ans,val);

        if(val>=maxx)
        {
            maxx=val;
            idxm=i;
        }
    }

    //cout<<m<<" "<<maxx<<" "<<idxm<<endl;
    div(l,m-1,optl,idxm);
    div(m+1,r,idxm,optr);
}

bool cmp(pair<long long,long long> p1,pair<long long,long long> p2)
{
    return p1.first>p2.first;
}

long long int findMaxAttraction(int N, int start, int D, int attraction[])
{
    n=N;
    d=D;
    s=start;

    for(long long i=0;i<n;i++)
    {
        a[i]=attraction[i];
        p[i]={a[i],i};
    }
    sort(p,p+n,cmp);

    for(long long i=0;i<n;i++)
        tidx[p[i].second]=i;

    update(1,0,n-1,tidx[0],1);
    div(s,n-1,0,s);

    reverse(a,a+n);
    for(long long i=0;i<n;i++)
        p[i]={a[i],i};
    sort(p,p+n,cmp);

    for(long long i=0;i<n;i++)
        tidx[p[i].second]=i;

    for(long long i=0;i<n;i++)
        update(1,0,n-1,i,0);

    update(1,0,n-1,tidx[0],1);
    fl=fr=0;
    s=n-s-1;
    div(s,n-1,0,s);
    return ans;
}

Compilation message (stderr)

holiday.cpp: In function 'void div(long long int, long long int, long long int, long long int)':
holiday.cpp:89:30: warning: unused variable 'last' [-Wunused-variable]
   89 |     long long maxx=-1,idxm=0,last=0;
      |                              ^~~~

• Subtask 1: 7 / 7
• Subtask 2: 23 / 23
• Subtask 3: 17 / 17
• Subtask 4: 53 / 53