Submission #754458

#	Time	Username	Problem	Language	Result	Execution time	Memory
754458		sheldon	Global Warming (CEOI18_glo)	C++14	100 / 100	53 ms	4424 KiB

glo

#include <bits/stdc++.h>

using namespace std;

void solve() {
    int n, x;
    cin >> n >> x;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }
    vector<int> dp;
    vector<int> longest(n);
    for (int i = 0; i < n; ++i) {
        auto it = lower_bound(dp.begin(), dp.end(), a[i]);
        if (it == dp.end()) {
            dp.push_back(a[i]);
            longest[i] = dp.size();
        } else {
            *it = a[i];
            longest[i] = it - dp.begin() + 1;
        }
    }
    dp.clear();
    int ans = 0;
    for (int i = n - 1; i >= 0; --i) {
        auto it = lower_bound(dp.begin(), dp.end(), -a[i] + x);
        ans = max(ans, int(it - dp.begin()) + longest[i]);
        it = lower_bound(dp.begin(), dp.end(), -a[i]); 
        if (it == dp.end()) dp.push_back(-a[i]);
        else *it = -a[i];
    }
    cout << ans;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    solve();
}

• 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