Submission #706710

#	Time	Username	Problem	Language	Result	Execution time	Memory
706710		Makarooni	Global Warming (CEOI18_glo)	C++17	100 / 100	130 ms	7844 KiB

glo

/* IN THE NAME OF GOD */
/* |\/| /-\ |\| | |\/| /-\ */

#include "bits/stdc++.h"
using namespace std;

#define sz(x) (int)x.size()
#define endl '\n'
#define pb push_back
#define all(x) x.begin(), x.end()
#define F first
#define S second
#define mr make_pair
//#define int long long
#define pii pair<int, int>
typedef long double ld;
typedef long long ll;

mt19937 rng (chrono::high_resolution_clock::now().time_since_epoch().count());

const int N = 4e5 + 10;
const int MOD = 1e9 + 7;
const int inf = 1e9 + 1;

int a[N], fen[N], l[N], r[N];
vector<int> vec, dp;

void upd(int p, int x){
	for(; p < N; p += p & -p)
		fen[p] = max(fen[p], x);
}

int get(int p){
	int ret = 0;
	for(; p > 0; p -= p & -p)
		ret = max(ret, fen[p]);
	return ret;
}

int f(int x){
	return lower_bound(all(vec), x) - vec.begin() + 1;
}

int32_t main(){
	ios_base:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
	int n, x;
	cin >> n >> x;
	for(int i = 1; i <= n; i++){
		cin >> a[i];
		vec.pb(a[i]);
		vec.pb(a[i] + x);
	}
	sort(all(vec));
	vec.resize(unique(all(vec)) - vec.begin());
	for(int i = 1; i <= n; i++){
		int t = lower_bound(all(dp), a[i]) - dp.begin();
		l[i] = t + 1;
		if(t < sz(dp))
			dp[t] = a[i];
		else
			dp.pb(a[i]);
	}
	reverse(a + 1, a + n + 1);
	for(int i = 1; i <= n; i++)
		a[i] *= -1;
	dp.clear();
	for(int i = 1; i <= n; i++){
		int t = lower_bound(all(dp), a[i]) - dp.begin();
		r[n - i + 1] = t + 1;
		if(t < sz(dp))
			dp[t] = a[i];
		else
			dp.pb(a[i]);
	}
	reverse(a + 1, a + n + 1);
	for(int i = 1; i <= n; i++)
		a[i] *= -1;
	int ans = 0;
	for(int i = 1; i <= n; i++){
		ans = max(ans, r[i] + get(f(a[i] + x) - 1));
		upd(f(a[i]), l[i]);
	}
	cout << ans;
}

• 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