Submission #1184784

#	Time	Username	Problem	Language	Result	Execution time	Memory
1184784		trvhung	Global Warming (CEOI18_glo)	C++20	100 / 100	90 ms	5948 KiB

glo

#include <bits/stdc++.h>
// #include <ext/rope>
// #include <ext/pb_ds/assoc_container.hpp>

// using namespace __gnu_pbds;
// using namespace __gnu_cxx;
using namespace std;

// #define   ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define            ll long long
#define           ull unsigned long long
#define            ld long double
#define            pb push_back
#define  bit(mask, i) ((mask >> i) & 1)
#define            el '\n'
#define             F first
#define             S second

template <class X, class Y> bool maximize(X &x, const Y &y) { return (x < y ? x = y, 1 : 0); }
template <class X, class Y> bool minimize(X &x, const Y &y) { return (x > y ? x = y, 1 : 0); }

const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 1e9 + 7;
const int MULTI = 0;
const ld eps = 1e-9;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0}; // R D L U
const int ddx[4] = {-1, 1, 1, -1}, ddy[4] = {1, 1, -1, -1}; // UR DR DL UL
const char cx[4] = {'R', 'D', 'L', 'U'};
const ll base = 31;
const int nMOD = 2;
const ll mods[] = {(ll)1e9 + 10777, (ll)1e9 + 19777, (ll)1e9 + 3, (ll)1e9 + 3777};

const int maxn = 2e5 + 5;
int n, x, a[maxn], id[maxn], lis[maxn], lds[maxn];

struct prefBIT {

	int bit[maxn];

	void update(int id, int v) {
		for (; id <= n; id += id & -id)
			maximize(bit[id], v);
	}

	int get(int id) {
		int res = 0;
		for (; id > 0; id -= id & -id)
			maximize(res, bit[id]);
		return res;
	}

} prefBIT;

struct sufBIT {

	int bit[maxn];

	void update(int id, int v) {
		for (; id > 0; id -= id & -id)
			maximize(bit[id], v);
	}

	int get(int id) {
		int res = 0;
		for (; id <= n; id += id & -id)
			maximize(res, bit[id]);
		return res;
	}

} sufBIT;

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

	vector<int> comp;
	for (int i = 1; i <= n; ++i) comp.push_back(a[i]);
	sort(comp.begin(), comp.end());
	comp.resize(unique(comp.begin(), comp.end()) - comp.begin());
	for (int i = 1; i <= n; ++i)
		id[i] = lower_bound(comp.begin(), comp.end(), a[i]) - comp.begin() + 1;

	for (int i = 1; i <= n; ++i) {
		lis[i] = prefBIT.get(id[i] - 1) + 1;
		prefBIT.update(id[i], lis[i]);
	}

	for (int i = n; i >= 1; --i) {
		lds[i] = sufBIT.get(id[i] + 1) + 1;
		sufBIT.update(id[i], lds[i]);
	}

	fill(sufBIT.bit + 1, sufBIT.bit + 1 + n, 0);

	int res = lis[n]; sufBIT.update(id[n], lds[n]);
	for (int i = n - 1; i >= 1; --i) {
		int l = upper_bound(comp.begin(), comp.end(), a[i] - x) - comp.begin() + 1;
		maximize(res, sufBIT.get(l) + lis[i]);
		sufBIT.update(id[i], lds[i]);
	}

	cout << res;
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    if (!MULTI) solve();
    else {
        int test; cin >> test;
        while (test--) solve();
    }
    
    return 0;
}

• 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