Submission #676581

#	Time	Username	Problem	Language	Result	Execution time	Memory
676581		benjaminkleyn	Split the sequence (APIO14_sequence)	C++17	28 / 100	2083 ms	2776 KiB

sequence

#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;

int N, K, a[100001];
ll pref[100001] = {0};
ll dp[2][100001] = {0};
int last_split[202][100001];

#define m(j) (pref[j])
#define c(j) (dp[0][j]-pref[j]*pref[N])

inline ll eval(const int &i, const ll &x)
{
    return m(i) * x + c(i);
}
 
int main()
{
    cin.tie(0)->sync_with_stdio(0);

    cin >> N >> K;
    for (int i = 1; i <= N; i++)
    {
         cin >> a[i];
         pref[i] = pref[i-1] + a[i];
    }
 
    for (int i = 0; i <= N; i++)
        dp[0][i] = pref[i] * (pref[N] - pref[i]);

    for (int k = 2; k <= K + 1; k++)
    {
        for (int i = k; i <= N; i++)
        {
            dp[1][i] = 0;
            for (int j = k - 1; j < i; j++)
                if (eval(j, pref[i]) > dp[1][i])
                {
                    dp[1][i] = eval(j, pref[i]);
                    last_split[k][i] = j;
                }
            dp[1][i] += pref[i] * (pref[N] - pref[i]);
        }
        for (int i = 1; i <= N; i++)
            dp[0][i] = dp[1][i];
    }

    cout << dp[0][N] << '\n';
    int i = N;
    do
    {
        i = last_split[K+1][i];
        cout << i << ' ';
    }
    while (--K);
    cout << '\n';
 
    return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 11 / 11
• Subtask 3: 0 / 11
• Subtask 4: 17 / 17
• Subtask 5: 0 / 21
• Subtask 6: 0 / 29