Submission #470289

#	Time	Username	Problem	Language	Result	Execution time	Memory
470289		mychecksedad	Global Warming (CEOI18_glo)	C++17	100 / 100	64 ms	5848 KiB

glo

#include<bits/stdc++.h>
using namespace std;
const int N = 2e5 + 10;
typedef long long int ll;
#define pb push_back
int n, ans = 0;
ll arr[N], x, dp[N];
int main(){
	cin.tie(0); ios::sync_with_stdio(0);
	cin >> n >> x;
	for(int i = 1; i <= n; i++) cin >> arr[i];
	vector<int> lis(1, 0);
	for(int j = 1; j <= n; j++){
		int pos = lower_bound(lis.begin(), lis.end(), arr[j]) - lis.begin();
		if(pos == int(lis.size())) lis.pb(arr[j]);
		else lis[pos] = arr[j];
		dp[j] = pos;
	}
	lis.clear();
	lis.pb(-1e9);
	for(int i = n; i >= 1; i--){
		int new_pos = lower_bound(lis.begin(), lis.end(), -(arr[i] - x)) - lis.begin();
		ans = max(ll(dp[i] + new_pos)-1, ll(ans));
		int pos = lower_bound(lis.begin(), lis.end(), -arr[i]) - lis.begin();
		if(pos == lis.size()) lis.pb(-arr[i]);
		else lis[pos] = -arr[i];
	}
	cout << ans;



	return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:25:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |   if(pos == lis.size()) lis.pb(-arr[i]);
      |      ~~~~^~~~~~~~~~~~~

• 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