Submission #933032

#	Time	Username	Problem	Language	Result	Execution time	Memory
933032		Edu175	Sequence (APIO23_sequence)	C++17	53 / 100	2079 ms	66528 KiB

sequence

#include "sequence.h"
#include <bits/stdc++.h>
#define pb push_back
#define fst first
#define snd second
#define fore(i,a,b) for(ll i=a,apio=b;i<apio;i++)
#define SZ(x) ((int)x.size())
#define ALL(x) x.begin(),x.end()
#define mset(a,v) memset((a),(v),sizeof(a))
#define imp(v) for(auto slkdh:v)cout<<slkdh<<" ";cout<<"\n"
using namespace std;
typedef int ll;
typedef pair<ll,ll> ii;

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
const ll INF=5e6;
struct node{
	ll mxp,mnp,mxs,mns,sum;
};
node oper(node a, node b){
	a.mxp=max(a.mxp,a.sum+b.mxp);
	a.mnp=min(a.mnp,a.sum+b.mnp);
	a.mxs=max(a.mxs+b.sum,b.mxs);
	a.mns=min(a.mns+b.sum,b.mns);
	a.sum+=b.sum;
	return a;
}
node NEUT({-INF,INF,-INF,INF,0});
struct STcustom{
	vector<node>t; ll n;
	STcustom(ll n):t(2*n+5,node({0,0,0,0,0})),n(n){}
	void upd(ll p, ll v){
		p+=n;
		t[p].mxp+=v,t[p].mnp+=v,t[p].mxs+=v,t[p].mns+=v,t[p].sum+=v;
		for(;p>1;p>>=1)p^=p&1,t[p>>1]=oper(t[p],t[p^1]);
	}
	node query(ll l, ll r){
		node izq=NEUT,der=NEUT;
		for(l+=n,r+=n;l<r;l>>=1,r>>=1){
			if(l&1)izq=oper(izq,t[l++]);
			if(r&1)der=oper(t[--r],der);
		}
		return oper(izq,der);
	}
};
const ll C=5e5,MAXN=2*C+5;
struct STree{
	vector<ll>t; ll n;
	STree(ll n):t(2*n+5,INF),n(n){}
	void upd(ll p, ll v){
		for(p+=n,t[p]=min(t[p],v);p>1;p>>=1)t[p>>1]=min(t[p],t[p^1]);
	}
	ll query(ll l, ll r){
		ll res=INF;
		for(l+=n,r+=n;l<r;l>>=1,r>>=1){
			if(l&1)res=min(res,t[l++]);
			if(r&1)res=min(res,t[--r]);
		}
		return res;
	}
};
ll l[MAXN],r[MAXN];
bool cmp(ll i, ll j){
	return ii({l[i],i})<ii({l[j],j});
}
const ll B=283;
int sequence(int N, std::vector<int> A) {
	ll n=N;
	vector<ll>a(n);
	fore(i,0,n)a[i]=A[i]-1;
	vector<ll>pos[n];
	fore(i,0,n)pos[a[i]].pb(i);
	STcustom st(n);
	fore(i,0,n)st.upd(i,1);
	ll res=1;
	vector<ll>s(n);
	fore(i,0,n)s[i]=1;
	fore(i,0,n)if(SZ(pos[i])){
		for(auto j:pos[i])st.upd(j,-1),s[j]--;
		if(SZ(pos[i])<B){
			fore(s,0,SZ(pos[i]))fore(e,s+1,SZ(pos[i])){
				ll l=pos[i][s],r=pos[i][e];
				ll dif=st.query(l,r+1).sum;
				node pre=st.query(0,l+1),suf=st.query(r,n);
				if(dif<=0){
					if(dif+pre.mxs+suf.mxp+e-s+1>=0)res=max(res,e-s+1);
				}
				else {
					if(dif+pre.mns+suf.mnp-(e-s+1)<=0)res=max(res,e-s+1);
				}
			}
		}
		else {
			ll sum=0,rew=0;
			vector<ll>rw(n+1);
			vector<ll>ev{n};
			l[n]=r[n]=rw[n]=0;
			fore(j,0,n){
				sum+=s[j],rew+=a[j]==i;
				rw[j]=rew;
				l[j]=sum-rew,r[j]=sum+rew;
				ev.pb(j);
			}
			sort(ALL(ev),cmp); reverse(ALL(ev));
			STree st(2*n+5+C);
			for(auto i:ev){
				res=max(res,rw[i]-st.query(0,r[i]+C+1));
				st.upd(r[i]+C,rw[i]);
			}
		}
		for(auto j:pos[i])st.upd(j,-1),s[j]--;
	}
	return res;
}

• Subtask 1: 11 / 11
• Subtask 2: 17 / 17
• Subtask 3: 0 / 7
• Subtask 4: 12 / 12
• Subtask 5: 13 / 13
• Subtask 6: 0 / 22
• Subtask 7: 0 / 18