Submission #734168

#	Time	Username	Problem	Language	Result	Execution time	Memory
734168		SanguineChameleon	Split the sequence (APIO14_sequence)	C++17	50 / 100	2082 ms	114032 KiB

sequence

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

void just_do_it();

int main() {
	#ifdef KAMIRULEZ
		freopen("kamirulez.inp", "r", stdin);
		freopen("kamirulez.out", "w", stdout);
	#endif
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	just_do_it();
	return 0;
}

const long long inf = 1e18L + 20;
const int maxN = 1e5 + 20;
const int maxK = 2e2 + 20;
int a[maxN];
long long pref[maxN];
long long dp[maxN][maxK];
int best[maxN][maxK];

struct line {
	long long a = 0;
	long long b = 0;

	line() {};

	line(long long _a, long long _b): a(_a), b(_b) {};

	long long eval(long long x) {
		return a * x + b;
	};
};

struct CHT {
	vector<pair<int, line>> Q;

	void add(int id, line L) {
		Q.emplace_back(id, L);
	}

	pair<int, long long> get(long long x) {
		long long mx = -inf;
		int best = -1;
		for (auto p: Q) {
			long long cur = p.second.eval(x);
			if (cur >= mx) {
				mx = cur;
				best = p.first;
			}
		}
		return make_pair(best, mx);
	}
};

CHT C[maxK];

void just_do_it() {
	int N, K;
	cin >> N >> K;
	for (int i = 1; i <= N; i++) {
		cin >> a[i];
		pref[i] = pref[i - 1] + a[i];
	}
	for (int j = 0; j <= K + 1; j++) {
		C[j].add(0, line(0, 0));
	}
	for (int i = 1; i <= N; i++) {
		for (int j = K + 1; j >= 1; j--) {
			auto p = C[j - 1].get(pref[i]);
			best[i][j] = p.first;
			dp[i][j] = p.second + pref[i] * (pref[N] - pref[i]);
			C[j].add(i, line(pref[i], dp[i][j] - pref[i] * pref[N]));
		}
	}
	cout << dp[N][K + 1] << '\n';
	int cur = N;
	for (int i = K + 1; i >= 2; i--) {
		cout << (cur = best[cur][i]) << " ";
	}
}

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