Submission #389003

#	Time	Username	Problem	Language	Result	Execution time	Memory
389003		phathnv	Split the sequence (APIO14_sequence)	C++11	100 / 100	1489 ms	81740 KiB

sequence

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

typedef long long ll;

const int N = 1e5 + 7;
const int K = 207;
const ll INF = 8e18;

int n, k, a[N], s[N];
ll dp[2][N];
int trace[K][N];

void Calc(int k, int l, int r, int from, int to){
    if (l > r)
        return;
    int mid = (l + r) >> 1;
    for(int i = from; i <= min(mid - 1, to); i++){
        ll cost = (ll) (s[mid] - s[i]) * (s[n] - s[mid]);
        if (dp[1][mid] < dp[0][i] + cost){
            dp[1][mid] = dp[0][i] + cost;
            trace[k][mid] = i;
        }
    }
    Calc(k, l, mid - 1, from, trace[k][mid]);
    Calc(k, mid + 1, r, trace[k][mid], to);
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

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

    for(int i = 0; i < 2; i++)
        for(int j = 0; j <= n; j++)
            dp[i][j] = -INF;
    dp[1][0] = 0;
    for(int i = 1; i <= k + 1; i++){
        for(int j = 0; j <= n; j++){
            dp[0][j] = dp[1][j];
            dp[1][j] = -INF;
        }
        Calc(i, 1, n, 0, n - 1);
    }
    cout << dp[1][n] << '\n';

    int cur = n;
    for(int i = k + 1; i > 1; i--){
        cur = trace[i][cur];
        cout << cur << ' ';
    }

    return 0;
}

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