Submission #1249216

#	Time	Username	Problem	Language	Result	Execution time	Memory
1249216		HiepVu217	Feast (NOI19_feast)	C++17	100 / 100	136 ms	35664 KiB

feast

#include <bits/stdc++.h>
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
using namespace std;
const int N = 3e5 + 17;
int n, k;
long long a[N];
pair <long long, int> f[N][7], m;
inline pair <long long, int> calc (long long c)
{
    f[1][0] = {0, 0}, f[1][1] = {a[1] - c, 1};
    for (int i = 2; i <= n; ++i)
    {
        f[i][0] = max (f[i - 1][0], f[i - 1][1]);
        f[i][1] = max (make_pair (f[i - 1][1].first + a[i], f[i - 1][1].second),
                       make_pair (f[i - 1][0].first + a[i] - c, f[i - 1][0].second + 1));
    }
    return max (f[n][0], f[n][1]);
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> k;
    for (int i = 1; i <= n; ++i)
    {
        cin >> a[i];
    }
    long long l = 1, r = 3e14;
    while (l < r)
    {
        long long mid = l + r + 1 >> 1;
        m = calc (mid);
        if (m.second >= k)
        {
            l = mid;
            continue;
        }
        r = mid - 1;
    }
    m = calc(l);
    long long ans = l * m.second + m.first;
    cout << ans;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 18 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 29 / 29