Submission #1230237

#	Time	Username	Problem	Language	Result	Execution time	Memory
1230237		vako_p	Sequence (APIO23_sequence)	C++20	69 / 100	2009 ms	76560 KiB

sequence

#include "sequence.h"
#include <bits/stdc++.h> 
using namespace std;
#define ll int
#define pb push_back
#define ff first
#define sd second
#define debug(x) cerr << #x << "----> " << x << endl;
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("O3")

const int mxN = 5e5 + 5;
ll n,a[mxN];

struct segtree{
	vector<ll> mn,mx,v1,b;
	ll sz = 1,inf = 1e9;
	
	void init(){
		while(sz < n + 5) sz *= 2;
		v1.assign(2 * sz, 0LL);
		mn.assign(2 * sz, 0LL);
		mx.assign(2 * sz, 0LL);
		for(int i = sz - 1; i < 2 * sz; i++) mx[i] = mn[i] = i - sz + 1;
		for(int i = sz - 2; i >= 0; i--){
			mx[i] = max(mx[2 * i + 2], mx[2 * i + 1]);
			mn[i] = min(mn[2 * i + 2], mn[2 * i + 1]);
		}
		b.assign(n + 5, 1LL);
		b[0] = 0;
	}
	
	void f(ll x){
		mx[x] += v1[x];
		mn[x] += v1[x];
		if(x < sz - 1){
			v1[2 * x + 1] += v1[x];
			v1[2 * x + 2] += v1[x];
		}
		v1[x] = 0;
	}
	
	void set(ll val, ll l, ll r, ll x, ll lx, ll rx){
		f(x);
		if(lx >= r or rx <= l) return;
		if(lx >= l and rx <= r){
			v1[x] += val;
			f(x);
			return;
		}
		ll mid = lx + (rx - lx) / 2;
		set(val, l, r, 2 * x + 1, lx, mid);
		set(val, l, r, 2 * x + 2, mid, rx);
		mx[x] = max(mx[2 * x + 1], mx[2 * x + 2]);
		mn[x] = min(mn[2 * x + 1], mn[2 * x + 2]);
	}
	
	void set(ll val, ll i){
		set(val - b[i], i, n + 1, 0, 0, sz);
		b[i] = val;
	}
	
	pair<ll,ll> find(ll l, ll r, ll x, ll lx, ll rx){
		f(x);
		if(lx >= r or rx <= l) return {1e9, -1e9};
		if(lx >= l and rx <= r) return {mn[x], mx[x]};
		ll mid = lx + (rx - lx) / 2;
		pair<ll,ll> k = find(l, r, 2 * x + 1, lx, mid),k1 = find(l, r, 2 * x + 2, mid, rx);
		return {min(k.ff, k1.ff), max(k.sd, k1.sd)};
	}
	
	pair<ll,ll> find(ll l, ll r){
		return find(l, r, 0, 0, sz);
	}
};

int sequence(int N, std::vector<int> A) {
  	n = N;
  	for(int i = 1; i <= n; i++) a[i] = A[i - 1];
  	segtree s,s1,s2;
	s.init();
	s1.init();
	s2.init();
	vector<ll> v[n + 1];
	for(int i = 1; i <= n; i++){
		v[a[i]].pb(i);
	}
	ll ans = 1;
	for(int i = 1; i <= n; i++){
		ll r1 = ans - 1;
		vector<ll>& vv = v[i];
		if(r1 < vv.size()){
			for(auto it : vv){
				s.set(0, it);
				s2.set(-1, it);
			}
			bool ok = false;
			pair<ll,ll> x,y;
			for(int l1 = 0; l1 < vv.size() and r1 < vv.size(); l1++){
				int l = vv[l1],r = vv[r1];
				if(!ok) x = s.find(0, l);
				y = s.find(r, n + 1);
				ok = false;
				if(x.sd <= y.sd){
					if(s2.find(r, n + 1).ff + l1 <= x.sd) ok = true;
				}
				else{
					if(x.ff <= s1.find(r, n + 1).sd - l1) ok = true;
				}
				r1++;
				if(ok){
					ans = r1 - l1;
					l1--;
					continue;
				}
//				s1.set(0, l);
//				s2.set(0, l);
			}
			for(auto it : vv){
				s.set(-1, it);
				s1.set(-1, it);
	//			s2.set(-1, it);
			}
		}
		else{
			for(auto it : vv){
			s.set(-1, it);
			s1.set(-1, it);
			s2.set(-1, it);
		}
		}
	}
	return ans;
}

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