Submission #375988

#	Time	Username	Problem	Language	Result	Execution time	Memory
375988		hivakarami	Global Warming (CEOI18_glo)	C++14	100 / 100	228 ms	8536 KiB

glo

#include<bits/stdc++.h>
 
using namespace std;
 
typedef long long int ll;
typedef long double ld;
#define f first
#define s second
 
const int N = 2e5 + 100;
const ll mod = 1e9 + 7;
const ll inf = 1e9 + 100;

int dp[N], a[N], l[N], r[N], n, x, seg[4*N];
vector<int> v;

int get(int L, int R, int b = 0, int e = n, int ind = 1)
{
	if(R <= b || e <= L)	
		return 0;
	if(L <= b && e <= R)
		return seg[ind];	
	
	int mid = (b + e) / 2;
		
	return max(get(L, R, mid, e, ind*2+1), get(L, R, b, mid, ind*2));
		
}

void add(int k, int val, int b = 0, int e = n, int ind = 1)
{
	if(b + 1 == e)
	{
		seg[ind] = val;
		return;
	}
	
	int mid = (b + e) / 2;
	if(k < mid)
		add(k, val, b, mid, ind*2);
	else
		add(k, val, mid, e, ind*2+1);
		
	seg[ind] = max(seg[ind*2], seg[ind*2+1]);	
}






int main()
{
    ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);	
	
	cin >> n >> x;
	for(int i = 0; i < n; i++)
	{
		cin >> a[i];
		v.push_back(a[i]);
	}
	sort(v.begin(), v.end());
	
	
	int p = 1;
	for(int i = 0; i < n; i++)
	{
		int j = lower_bound(dp, dp+p, a[i]) - dp;
		dp[j] = a[i];
		p = max(p, j+1);
		l[i] = j;
	}
	//cout << p - 1 << endl;
	
	for(int i = 0; i < n; i++)
		dp[i] = -inf;


	p = 1;
	for(int i = n-1; i >= 0; i--)
	{
		int j = lower_bound(dp, dp+p, -a[i]) - dp;
		dp[j] = -a[i];
		p = max(p, j+1);
		r[i] = j;
		//cout << r[i] << endl;
	}
		
		
	
	int ans = 1;
	for(int i = 0; i < n; i++)
	{
		int id = lower_bound(v.begin(), v.end(), a[i]+x) - v.begin();
		int mx = get(0, id);
		ans = max(ans, r[i] + mx);
		id = lower_bound(v.begin(), v.end(), a[i]) - v.begin();
		add(id, l[i]);
	}
	
	
	cout << ans << endl;


	return 0;
}

/*
8 10
7 3 5 12 2 7 3 4
*/

• 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