Submission #382280

#	Time	Username	Problem	Language	Result	Execution time	Memory
382280		ijxjdjd	Split the sequence (APIO14_sequence)	C++14	71 / 100	2033 ms	85068 KiB

sequence

#include <bits/stdc++.h>
#define FR(i, N) for (int i = 0; i < int(N); i++)
#define all(x) begin(x), end(x)

using namespace std;

using ll = long long;

const int MAXN = (int)(1e5) + 5;
const int MAXK = 200+5;
int opt[MAXN][MAXK];
ll last[MAXN];
ll dp[MAXN];
//ll dp[MAXN][MAXK];
ll arr[MAXN];
ll prefSum[MAXN];
ll pref[MAXN];
ll calc(int l, int r) {
    if (l == 0) {
        return pref[r];
    }
    else {
        return pref[r] - (prefSum[r]-prefSum[l-1])*prefSum[l-1] - pref[l-1];
    }
}
void recur(int k, int tl, int tr, int l, int r) {
    if (tl > tr) {
        return;
    }
    int tm = (tl + tr)/2;
    ll best = (ll)(1e18);
    int id = -1;
    for (int i = min(r, tm-1); i >= l; i--) {
        if (last[i] + calc(i+1, tm) < best) {
            best = last[i] + calc(i+1, tm);
            id = i;
        }
    }
    opt[tm][k] = id;
    dp[tm] = best;
    recur(k, tl, tm-1, l, id);
    recur(k, tm+1, tr, id, r);
}
int main() {
	cin.tie(0);
	cin.sync_with_stdio(0);
	int N, K;
	cin >> N >> K;
	ll sm = 0;
	FR(i, N) {
        cin >> arr[i];
        last[i] = (i > 0 ? last[i-1] : 0) + arr[i]*sm;
        pref[i] = last[i];
        opt[i][0] = -1;
        sm += arr[i];
        prefSum[i] = sm;
	}
	for (int i = 1; i <= K; i++) {
        recur(i, 0, N-1, 0, N-1);
        swap(dp, last);
	}
	cout << pref[N-1] - last[N-1] << '\n';
	int u = N-1;
	for (int iter = K; iter >= 1; iter--) {
        cout << opt[u][iter]+1 << '\n';
        u = opt[u][iter];
	}
	return 0;
}

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