Submission #1023837

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023837		NValchanov	Global Warming (CEOI18_glo)	C++17	38 / 100	2063 ms	4700 KiB

glo

#include <bits/stdc++.h>

#define endl '\n'

using namespace std;

typedef long long ll;

const int MAXN = 2e5 + 10;
const int MAXA = 1e9 + 10;
const int MAXX = 1e9 + 10;

int n, x;
vector < int > a;
vector < int > tmp;

void read()
{
    cin >> n >> x;
    a.resize(n);
    for(int i = 0; i < n; i++)
    {
        cin >> a[i];
    }
}

int lis(vector < int > arr)
{
    vector < int > lissy;
    lissy.resize(n + 1);
    lissy[0] = -MAXA;
    lissy[1] = arr[0];

    int ans = 1;

    for(int i = 1; i < n; i++)
    {
        int j = lower_bound(lissy.begin(), lissy.begin() + ans + 1, arr[i]) - lissy.begin();

        ans = max(ans, j);

        lissy[j] = arr[i];
    }

    return ans;
}

int solve_slow()
{
    int ans = lis(a);

    for(int i = 0; i < n; i++)
    {
        tmp = a;

        for(int j = 0; j <= i; j++)
        {
            tmp[j] -= x;
        }

        ans = max(ans, lis(tmp));
    }

    for(int i = n - 1; i >= 0; i--)
    {
        tmp = a;

        for(int j = n - 1; j >= i; j--)
        {
            tmp[j] += x;
        }

        ans = max(ans, lis(tmp));
    }

    return ans;
}

void solve()
{
    if(x == 0)
        cout << lis(a) << endl;
    else
        cout << solve_slow() << endl;
}

int main()
{
    ios_base :: sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    read();
    solve();

    return 0;
}

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