Submission #1263292

#	Time	Username	Problem	Language	Result	Execution time	Memory
1263292		kaloyan	Global Warming (CEOI18_glo)	C++20	28 / 100	2095 ms	4932 KiB

glo

#include <bits/stdc++.h>

using namespace std;

#define int long long

const int MAXN = 2e5 + 10;
const int INF = 1e18;

int n, x;
int a[MAXN], temp[MAXN], dp[MAXN];
int best = 0;

int lower_binary(int x)
{
    int l = -1, r = n;
    
    while(r > l + 1)
    {
        int m = (l + r) / 2;

        if(dp[m] >= x)
        {
            r = m;
        }
        else
        {
            l = m;
        }
    }

    return r;
}

int lis(int r, int x)
{
    int ret = 0;

    for(int i = 0 ; i < n ; ++i)
    {
        temp[i] = a[i];
    }

    for(int i = 0 ; i <= r; ++i)
    {
        temp[i] += x;
    }

    dp[0] = -INF;

    for(int i = 1 ; i <= n ; ++i)
    {
        dp[i] = INF;
    }

    for(int i = 0 ; i < n ; ++i)
    {
        int idx = lower_binary(temp[i]);

        dp[idx] = temp[i];

        ret = max(ret, idx);
    }

    return ret;
}

void solve()
{
    cin >> n >> x;

    for(int i = 0 ; i < n ; ++i)
    {
        cin >> a[i];
    }

    for(int r = 0 ; r < n ; ++r)
    {
        best = max(best, lis(r, -x));
    }
    

    cout << best << "\n";
}

void fastIO()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}

signed main()
{
    fastIO();
    solve();
}

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