Submission #437587

#	Time	Username	Problem	Language	Result	Execution time	Memory
437587		soroush	Split the sequence (APIO14_sequence)	C++11	100 / 100	1071 ms	81044 KiB

sequence

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int maxn = 1e5 + 10;

int n, k;
ll dp[maxn][2];
ll prt[maxn];
int par[207][maxn];

void solve(int k, int l = 1 , int r = n , int ul = 1 , int ur = n){
	if(l > r)return;
	if(l == r){
		for(int i = ul ; i <= ur and i < l ; i ++){
			ll res = dp[i][!(k&1)];
			res += (prt[l] - prt[i]) * (prt[n] - prt[l]);
			if(res > dp[l][k&1]){
				dp[l][k&1] = res;
				par[k][l] = i;
			}
		}
	}
	int mid = (l + r) / 2;
	for(int i = ul ; i <= ur and i < mid ; i ++){
		ll res = dp[i][!(k&1)];
		res += (prt[mid] - prt[i]) * (prt[n] - prt[mid]);
		if(res >= dp[mid][k&1]){
			dp[mid][k&1] = res;
			par[k][mid] = i;
		}
	}
	solve(k, l, mid - 1 , ul, par[k][mid]);
	solve(k, mid + 1 , r , par[k][mid], ur);
}

int32_t main(){
	ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	cin >> n >> k;
	for(int i = 1 ; i <= n ; i ++)
		cin >> prt[i], prt[i] += prt[i - 1];
	for(int i = 1 ; i <= k ; i ++)
		solve(i , i  , n-1 , i-1 , n-1);
	int ans = 1;
	for(int i = 1 ; i <= n ; i ++)if(dp[i][k&1] > dp[ans][k&1])ans = i;
	cout << dp[ans][k&1] << endl;
	cout << ans;
	while(k > 1){
		cout << ' ' << par[k][ans];
		ans = par[k][ans] , k --;
	}
	return(0);
}

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