Submission #385793

#	Time	Username	Problem	Language	Result	Execution time	Memory
385793		SansPapyrus683	Global Warming (CEOI18_glo)	C++17	27 / 100	131 ms	2728 KiB

glo

#include <bits/stdc++.h>

using namespace std;

int temps[200005];
int pref_longest[200005];

int main() {
    int n;
    int x;
	cin >> n >> x;
	for (int i = 0; i < n; i++) {
        cin >> temps[i];
    }
    
	vector<int> dp(n, INT_MAX);
	int longest = 0;
	// longest increasing subsequence ending at i
	for (int i = 0; i < n; i++) {
		int j = lower_bound(dp.begin(), dp.end(), temps[i]) - dp.begin();
		dp[j] = temps[i];
		pref_longest[i] = j + 1;
		longest = max(longest, pref_longest[i]);
	}

	dp.assign(n,INT_MAX);
	// longest decreasing subsequence ending at i of reverse array
	// = longest increasing subsequence starting at i
	for (int i = n - 1; i >= 0; i--) {
		int jj = lower_bound(dp.begin(), dp.end(), -temps[i]) - dp.begin();
		dp[jj] = -temps[i];

		int j = lower_bound(dp.begin(), dp.end(), -temps[i] + x) - dp.begin();
        longest = max(longest, pref_longest[i] + j);
	}
	cout << longest << endl;
}

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