Submission #670113

#	Time	Username	Problem	Language	Result	Execution time	Memory
670113		NothingXD	Split the sequence (APIO14_sequence)	C++17	71 / 100	2089 ms	81048 KiB

sequence

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

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
/*typedef __uint128_t L;
struct FastMod {
  ull b, m;
  FastMod(ull b) : b(b), m(ull((L(1) << 64) / b)) {}
  ull reduce(ull a) {
    ull q = (ull)((L(m) * a) >> 64);
    ull r = a - q * b; // can be proven that 0 <= r < 2*b
    return r >= b ? r - b : r;
  }
};
FastMod FM(2);*/
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

void debug_out() { cerr << endl; }

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
	cerr << " " << H;
	debug_out(T...);
}

#define debug(...) cerr << "(" << #__VA_ARGS__ << "):", debug_out(__VA_ARGS__)
#define all(x) x.begin(), x.end()
#define MP(x, y) make_pair(x, y)
#define F first
#define S second

//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int maxn = 1e5 + 10;
const int maxk = 200 + 10;
const ll inf = 1e18;
int n, k, a[maxn], sum, L, R, flg[maxk][maxn];
ll val, dp[2][maxn];

inline void add(int i){
	val += 1ll * sum * a[i];
	sum += a[i];
}

inline void remove(int i){
	sum -= a[i];
	val -= 1ll * sum * a[i];
}

inline ll get(int l, int r){
	while(l < L){
		L--;
		add(L);
	}
	while(R < r){
		R++;
		add(R);
	}
	while(L < l){
		remove(L);
		L++;
	}
	while(r < R){
		remove(R);
		R--;
	}
	return val;
}

void solve(int x, int l, int r, int ql, int qr){
	int PTR = (x&1);
	int PRV = 1 - PTR;
	if (r < l) return;
	int mid = (l + r) >> 1;
	dp[PTR][mid] = dp[PRV][min(mid-1, qr)] + get(min(mid-1, qr) + 1, mid);
	int ptr = min(mid - 1, qr);
	for (int i = min(mid-1, qr) - 1; i >= ql; i--){
		ll tmp = dp[PRV][i] + get(i+1, mid);
		if (tmp < dp[PTR][mid]){
			dp[PTR][mid] = tmp;
			ptr = i;
		}
	}
	flg[x][mid] = ptr;
	solve(x, l, mid-1, ql, ptr);
	solve(x, mid+1, r, ptr, qr);
}

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

	cin >> n >> k;

	for (int i = 1; i <= n; i++) cin >> a[i];
	
	ll ans = 0;
	int sum = 0;
	for (int i = 1; i <= n; i++){
		ans += 1ll * sum * a[i];
		sum += a[i];
		dp[0][i] = ans;
	}

	for (int i = 1; i <= k; i++){
		solve(i, 1, n, 0, n);
	}


	cout << ans - dp[(k&1)][n] << '\n';


	int ptr = n;
	int tmp = k;
	while(tmp){
		cout << flg[tmp][ptr] << ' ';
		ptr = flg[tmp][ptr];
		tmp--;
	}
	cout << '\n';
	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