Submission #444986

#	Time	Username	Problem	Language	Result	Execution time	Memory
444986		Nima_Naderi	Global Warming (CEOI18_glo)	C++14	100 / 100	254 ms	19652 KiB

glo

//In the name of GOD
//#pragma GCC optimize("O2")
#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
const ll MXN = 1e6 + 10;
const ll INF = 1e18;
ll n, d, lans, ans;
ll A[MXN], B[MXN], M[MXN], Mp[MXN];
ll dp[MXN], mx[MXN], rig[MXN];
vector<ll> Num;
ll GetId(ll x){
	return lower_bound(Num.begin(), Num.end(), x) - Num.begin() + 1;
}
void LIS(ll up, bool f){
	dp[0] = -INF, mx[0] = lans = 0;
	for(int i = 1; i <= up; i ++) dp[i] = INF;
	for(int i = 1; i <= up; i ++){
		if(f) rig[n - i + 1] = lower_bound(dp, dp + lans + 1, Mp[i]) - dp;
		mx[i] = lower_bound(dp, dp + lans + 1, M[i]) - dp;
		if(!f) ans = max(ans, mx[i] + rig[i] - 1);
		lans = max(lans, mx[i]);
		dp[mx[i]] = M[i];
	}
}
int main(){
	ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
	cin >> n >> d;
	for(int i = 1; i <= n; i ++){
		cin >> A[i], B[i] = A[i] - d;
		Num.push_back(A[i]);
		Num.push_back(B[i]);
		Num.push_back(-A[i]);
		Num.push_back(-B[i]);
	}
	sort(Num.begin(), Num.end());
	Num.resize(unique(Num.begin(), Num.end()) - Num.begin());
	for(int i = 1; i <= n; i ++) M[i] = GetId(-A[n - i + 1]);
	for(int i = 1; i <= n; i ++) Mp[i] = GetId(-B[n - i + 1]);
	LIS(n, 1);
	for(int i = 1; i <= n; i ++) M[i] = GetId(A[i]);
	LIS(n, 0);
	ans = max(ans, lans);
	cout << ans << '\n';
	return 0;
}
// NNG

• 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