Submission #1305547

#	Time	Username	Problem	Language	Result	Execution time	Memory
1305547		liangjeremy	Global Warming (CEOI18_glo)	C++20	100 / 100	185 ms	20940 KiB

glo

#include<bits/stdc++.h>
#include<bits/extc++.h>
#define fi first
#define se second
#define int long long
using namespace std;
//using namespace __gnu_pbds;
using db=double;
using ll=int64_t;
using sll=__int128;
using lb=long double;
mt19937 rng(random_device{}()); 

struct segtree{
	vector<int>mx; 
	segtree(int n){
		mx.resize(n<<2); 
	}
	void update(int l, int r, int rt, int idx, int val){
		if(l==r){
			mx[rt]=max(mx[rt],val); return;
		}
		int mid=(l+r)>>1; 
		if(idx<=mid)update(l,mid,rt<<1,idx,val); 
		else update(mid+1,r,rt<<1|1,idx,val); 
		mx[rt]=max(mx[rt<<1],mx[rt<<1|1]); 
	}
	int query(int l, int r, int rt, int L, int R){
		if(L<=l && r<=R)return mx[rt]; 
		int ans=0; int mid=(l+r)>>1; 
		if(L<=mid)ans=max(ans,query(l,mid,rt<<1,L,R)); 
		if(R>mid)ans=max(ans,query(mid+1,r,rt<<1|1,L,R)); 
		return ans; 
	}
};

int32_t main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	int n,x; cin>>n>>x; vector<int>a(n+1); vector<int>v; vector<int>a2(n+1); 
	for(int i=1; i<=n; i++){ cin>>a[i]; v.push_back(a[i]); }
	sort(v.begin(),v.end()); v.erase(unique(v.begin(),v.end()),v.end()); 
	for(int i=1; i<=n; i++){
		a2[i]=a[i]; a[i]=lower_bound(v.begin(),v.end(),a[i])-v.begin()+1; 
	}
	vector<int>pre(n+1); segtree segl(n+20); 
	for(int i=1; i<=n; i++){
		pre[i]=segl.query(0,n+1,1,0,a[i]-1)+1; segl.update(0,n+1,1,a[i],pre[i]); 
	}
	int ans=segl.query(0,n+1,1,0,n+1); vector<int>suf(n+1); segtree segr(n+20); 
	for(int i=n; i>=1; i--){
		suf[i]=segr.query(0,n+1,1,a[i]+1,n+1)+1; segr.update(0,n+1,1,a[i],suf[i]); 
		int idx=lower_bound(v.begin(),v.end(),a2[i-1]-x+1)-v.begin()+1; 
		ans=max(ans,pre[i-1]+segr.query(0,n+1,1,idx,n+1)); 
	}
	cout<<ans<<'\n'; 
}
/*
Overhead the albatross hangs motionless upon the air
And deep beneath the rolling waves in labyrinths of coral caves
The echo of a distant time comes willowing across the sand
And everything is green and submarine
 
And no one showed us to the land
And no one knows the wheres or whys
But something stirs and something tries
And starts to climb towards the light
*/

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