Submission #397054

#	Time	Username	Problem	Language	Result	Execution time	Memory
397054		huukhang	Global Warming (CEOI18_glo)	C++11	37 / 100	72 ms	2664 KiB

glo

// - Only when necessary :d
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("avx,avx2,fma")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

#define fileopen(a, b) freopen(((string)a + ".inp").c_str(), "r", stdin); freopen(((string)b + ".out").c_str(), "w", stdout); 

#define ll long long
// #define int long long
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define pob pop_back
#define pof pop_front
typedef pair<int, int> pii;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

const ll mod = 1e9 + 7;
const ll inf = 1e9 + 7;
const double eps = 1e-9;

int n, x;
int a[200005];
int dp[200005], pmx[200005];
int ans = -inf;

void solve() {
	cin >> n >> x;
	for (int i = 1; i <= n; ++i) cin >> a[i];

	dp[0] = -inf;
	for (int i = 1; i <= n; ++i) dp[i] = inf;

	for (int i = 1; i <= n; ++i) {
		int idx = upper_bound(dp + 1, dp + n + 1, a[i]) - dp;
		if (dp[idx - 1] < a[i]) dp[idx] = a[i];

		pmx[i] = idx;
	}

	dp[0] = -inf;
	for (int i = 1; i <= n; ++i) dp[i] = inf;

	for (int i = n; i >= 1; --i) {
		int idx = lower_bound(dp + 1, dp + n + 1, -a[i] + x) - dp;
		ans = max(ans, pmx[i] + idx - 1);

		idx = lower_bound(dp + 1, dp + n + 1, -a[i]) - dp;
		if (dp[idx - 1] < -a[i] + x) dp[idx] = -a[i];
	}

	cout << ans;
}

signed main() {
	#ifdef khangorz
		fileopen("input", "output");
	#endif
	#ifndef khangorz
//		fileopen("LAH", "LAH");
	#endif
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	solve();
	return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 13
• Subtask 4: 0 / 10
• Subtask 5: 20 / 20
• Subtask 6: 17 / 17
• Subtask 7: 0 / 25