Submission #231990

#	Time	Username	Problem	Language	Result	Execution time	Memory
231990		ruler	Split the sequence (APIO14_sequence)	C++14	89 / 100	1498 ms	81016 KiB

sequence

// IOI 2021
#include <bits/stdc++.h>
using namespace std;

#define endl '\n'
#define ends ' '
#define die(x) return cout << x << endl, 0
#define all(v) v.begin(), v.end()
#define sz(x) (int)(x.size())
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) { cerr << ends << H; debug_out(T...); }
#define debug(...) cerr << "{" << #__VA_ARGS__ << "}:", debug_out(__VA_ARGS__)
typedef long long ll;
typedef pair<int, int> pii;
const int INF = 2e9;
const ll MOD = 1e9 + 7;
 
////////////////////////////////////////////////////////////////////

const int N = 1e5 + 5, K = 2e2 + 5;

int PS[N], OPT[K][N];
ll DP[2][N];

ll C(int l, int r) { return 1LL * (PS[r] - PS[l - 1]) * (PS[r] - PS[l - 1]); }
void DQ(int l, int r, int s, int e, int k) {
	if (r < l) return;
	int md = (l + r) >> 1, &opt = OPT[k][md];
	for (int i = s; i <= min(e, md); i++)
		if (DP[k & 1][md] > DP[(k & 1) ^ 1][i - 1] + C(i, md))
			DP[k & 1][md] = DP[(k & 1) ^ 1][i - 1] + C(i, md), opt = i;
	DQ(l, md - 1, s, opt, k), DQ(md + 1, r, opt, e, k);
}

int main() {

	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	mt19937 Rnd(time(0));

	memset(DP, 63, sizeof DP); DP[0][0] = 0;

	int n, k; cin >> n >> k; k++;
	for (int i = 1; i <= n; i++) cin >> PS[i], PS[i] += PS[i - 1];
	for (int i = 1; i <= k; i++) DQ(i, n, i, n, i);
	cout << (C(1, n) - DP[k & 1][n]) / 2 << endl;
	while (k > 1) cout << OPT[k][n] - 1 << ends, n = OPT[k][n] - 1, k--;
	cout << endl;
		
	return 0;
}

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