Submission #328367

#	Time	Username	Problem	Language	Result	Execution time	Memory
328367		Sara	Global Warming (CEOI18_glo)	C++14	100 / 100	131 ms	2796 KiB

glo

#include <bits/stdc++.h>
     
using namespace std;
     
#define ll long long int 
#define F first
#define S second
#define pb push_back

const ll N = 2e5 + 10;
const ll M = 50;
const ll MOD = 1e9 + 7;
const ll INF = 1e9 + 10;
int n, X, a[N], l[N], r[N], f[N], ans;
int main() {
    cin >> n >> X;
    int len = 0;
    for (int i = 0; i < n; i++){
        cin >> a[i];
        int p = lower_bound(l, l + len, a[i]) - l;
        l[p] = a[i];
        len = max(len, p + 1);
        f[i] = p + 1;
    }
    ans = f[n - 1];
    len = 0;
    for (int i = n - 1; i >= 0; i--){
        a[i] *= -1;
        int p = upper_bound(r, r + len, a[i] - 1) - r;
        ans = max(ans, f[i] + p);
        a[i] -= X;
        p = lower_bound(r, r + len, a[i]) - r;
        r[p] = a[i];
        len = max(len, p + 1);
    }
    cout << ans << '\n';
    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