Submission #1205749

#	Time	Username	Problem	Language	Result	Execution time	Memory
1205749		asli_bg	Global Warming (CEOI18_glo)	C++20	15 / 100	232 ms	327680 KiB

glo

#include <bits/stdc++.h>
using namespace std;
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;

#define int long long
 
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<bool> vb;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef vector<pll> vll;
 
typedef tree<pii,null_type,less<pii>,rb_tree_tag,
tree_order_statistics_node_update> oset;
 
#define fi first
#define se second
#define pb push_back
#define pf push_front
 
#define mid (l+r)/2
#define all(x) x.begin(),x.end()
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)
 
#define cont(x) for(auto el:x) cout<<el<<' ';cout<<endl;
#define contp(x) for(auto el:x) cout<<el.fi<<'-'<<el.se<<' ';cout<<endl;
#define sp <<" "<<
 
#define DEBUG(x) cout<<(#x) sp x<<endl
#define carp(a,b) (((a%MOD)*(b%MOD))%MOD)
#define topla(a,b) (((a%MOD)+(b%MOD))%MOD)
 
const ll INF=1e18;
const int MAXN=1e6+5;
const int MAXK=30;
const int MOD=1e9+7;

oset tut[MAXN];

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int n,x;
    cin>>n>>x;

    vi a(n+1);
    FORE(i,1,n+1) cin>>a[i];

    int ans;

    //pref
    FORE(i,1,n+1) a[i]-=x;

    oset pref;

    FORE(i,1,n+1){
        if(pref.empty()){
            pref.insert({a[i],i});
        }
        else{
            auto it=pref.upper_bound({a[i],0});
            if(it!=pref.end()){ 
                pref.erase(*it);
            }
            pref.insert({a[i],i});
        }
        tut[i]=pref;
    }

    //contp(pref);
    ans=pref.size();

    //suf
    FORE(i,1,n+1){
        a[i]+=x;
        a[i]*=-1;
    }

    //cont(a);

    oset suf;

    for(int i=n;i>0;i--){
        if(suf.empty()){
            suf.insert({a[i],i});
        }
        else{
            auto it=suf.upper_bound({a[i],0});
            if(it!=suf.end()){ 
                suf.erase(*it);
            }
            suf.insert({a[i],i});
        }

        if(i-1>0){
            int deg=tut[i-1].rbegin()->fi;
            /*DEBUG(deg);

            contp(suf);
            contp(tut[i-1]);*/

            int ind=suf.order_of_key({-deg,0});
            //DEBUG(ind);
            ans=max(ans,(int) tut[i-1].size()+ind);

            deg=suf.begin()->fi;
            ind=tut[i-1].order_of_key({deg,0});

            ans=max(ans,(int) suf.size()+ind);
        }
    }

    //contp(suf);

    cout<<ans<<endl;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 17
• Subtask 7: 0 / 25