Submission #231968

#	Time	Username	Problem	Language	Result	Execution time	Memory
231968		Atalasion	Split the sequence (APIO14_sequence)	C++14	49 / 100	109 ms	131076 KiB

sequence

//khodaya khodet komak kon
#include <bits/stdc++.h>

#define F first
#define S second
#define pb push_back
#define all(x) x.begin(), x.end()
#pragma GCC optimise ("ofast")
#pragma GCC optimise("unroll-loops")
#define int long long

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

const int N = 100000 + 10;
const ll MOD = 1000000000 + 7;
const ll INF = 1000000000000000000;
const ll LOG = 25;

int n, k, a[N], ps[N], opt[N][210];
ll dp[N][2];

ll cost (int l, int r){
	ll x = ps[r] - ps[l - 1];
	return x * x;
}

int solve(int l, int r, int lq, int rq, int x, int f){
	if (rq < lq) return 0;
	int md = (lq + rq) >> 1;
	for (int i = l; i < min(r + 1, md); i++){
		if (dp[md][f] > dp[i][f ^ 1] + cost(i + 1, md)){
			dp[md][f] = dp[i][f ^ 1] + cost(i + 1, md);
			opt[md][x] = i;
		}
	}	
	//cout << opt[md][x] << '\n';
	if (lq == rq) return 0;
	solve(l, opt[md][x], lq, md - 1, x,f);
	solve(opt[md][x], r, md + 1, rq, x,f);
}

int32_t main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> k;
	for (int i = 1; i <= n; i++){
		cin >> a[i];
		ps[i] = ps[i - 1] + a[i];
	}
	bool f = 0;
	for (int i = 1; i <= n; i++){
		dp[i][1] = ps[i] * ps[i];
	}
	for (int i = 2; i <= k + 1; i++){
		for (int j = 0; j < N; j++) dp[j][f] = INF;
		solve(1, n, 1, n, i, f);
		f ^= 1;
	}
	cout << (ps[n] * 1ll * ps[n] - dp[n][f ^ 1]) / 2<< '\n';
	vector<int> ans;
	int Now = n;
	for (int i = k + 1; i >= 2; i--){
		ans.pb(opt[Now][i]);
		Now = opt[Now][i];
	}
	reverse(all(ans));
	for (auto u:ans) cout << u << ' ';







	return 0;
}
/*
7 3
4 1 3 4 0 2 3
*/

Compilation message (stderr)

sequence.cpp:8:0: warning: ignoring #pragma GCC optimise [-Wunknown-pragmas]
 #pragma GCC optimise ("ofast")
 
sequence.cpp:9:0: warning: ignoring #pragma GCC optimise [-Wunknown-pragmas]
 #pragma GCC optimise("unroll-loops")
 
sequence.cpp: In function 'long long int solve(long long int, long long int, long long int, long long int, long long int, long long int)':
sequence.cpp:44:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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