Submission #1296432

#	Time	Username	Problem	Language	Result	Execution time	Memory
1296432		idk_anything_i_guess	Split the sequence (APIO14_sequence)	C++20	0 / 100	1 ms	332 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

// ---------- Global data ----------
const ll NEG = LLONG_MIN / 4;

int n, k;
vector<ll> a, s;
vector<ll> dp_prev, dp_cur;

void solve(int l, int r, int optL, int optR) {
    if (l > r) return;

    int mid = (l + r) >> 1;
    pair<ll,int> best = {NEG, -1};

    for (int j = optL; j <= min(mid-1, optR); j++) {
        ll val = dp_prev[j] + s[j] * (s[mid] - s[j]);
        if (val > best.first) best = {val, j};
    }

    dp_cur[mid] = best.first;
    int opt = best.second;

    solve(l, mid-1, optL, opt);
    solve(mid+1, r, opt, optR);
}

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

    cin >> n >> k;
    a.assign(n+1, 0);
    s.assign(n+1, 0);

    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) s[i] = s[i-1] + a[i];

    dp_prev.assign(n+1, 0);
    dp_cur.assign(n+1, 0);

    for (int t = 1; t <= k; t++) {
        solve(1, n, 0, n-1);
        dp_prev = dp_cur;
    }

    cout << dp_prev[n] << "\n";
    return 0;
}

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