Submission #113090

#	Time	Username	Problem	Language	Result	Execution time	Memory
113090		dolphingarlic	Split the sequence (APIO14_sequence)	C++14	11 / 100	38 ms	33192 KiB

sequence

#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#define FOR(i, x, y) for (int i = x; i < y; i++)
typedef long long ll;
using namespace std;
 
int n, k;
pair<ll, int> dp[201][100001];
int pref[100001]{0}, q[100001], l = 1, r = 1;
 
bool case1(int x, int y, int i, int indx) {
    return (dp[indx][y].first - dp[indx][x].first >=
            (pref[y] - pref[x]) * (pref[n] - pref[i]));
}
 
bool case2(int x, int y, int i, int indx) {
    return ((dp[indx][y].first - dp[indx][x].first) * (pref[i] - pref[y]) <=
            (dp[indx][i].first - dp[indx][y].first) * (pref[y] - pref[x]));
}
 
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n >> k;
    FOR(i, 1, n + 1) {
        int x;
        cin >> x;
        pref[i] = pref[i - 1] + x;
    }
 
    fill(dp[0], dp[0] + n + 1, make_pair(0, 0));
    FOR(i, 1, k + 1) {
        q[r++] = 0;
        dp[i][0] = {0, 0};
        FOR(j, 1, n + 1) {
            while (r - l > 1 && case1(q[l], q[l + 1], j, i - 1)) l++;
 
            ll x = q[l];
            dp[i][j] = {dp[i - 1][x].first + (ll)(pref[j] - pref[x]) * (ll)(pref[n] - pref[j]), x};
 
            while (r - l > 1 && case2(q[r - 2], q[r - 1], j, i - 1)) r--;
            q[r++] = j;
        }
        l = r = 1;
    }
 
    ll mx = -1;
    int indx = -1;
    FOR(i, 1, n + 1) {
        if (dp[k][i].first > mx) mx = dp[k][i].first, indx = i;
    }
    cout << mx << '\n';
    FOR(i, 0, k) {
        cout << indx << ' ';
        indx = dp[k - i][indx].second;
    }
    cout << '\n';
    return 0;
}

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