Submission #770710

#	Time	Username	Problem	Language	Result	Execution time	Memory
770710		OrazB	Split the sequence (APIO14_sequence)	C++14	11 / 100	5 ms	5588 KiB

sequence

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,
             tree_order_statistics_node_update>
    ordered_set;
//Dijkstra->set
//set.find_by_order(x) x-position value
//set.order_of_key(x) number of strictly less elements don't need *set.??
#define wr cout << "Continue debugging\n";
#define all(x) (x).begin(), (x).end()
#define ll long long int
#define pii pair <int, int>
#define pb push_back
#define ff first
#define ss second

const int N = 55;
const ll INF = 1e18;
int n, k, a[N];
ll pref[	N]; 
pair<ll, vector<int>> dp[N][N][N];

pair<ll, vector<int>> F(int l, int r, int k){
	if (l == r or k <= 0) return {0, {}};
	ll mx = -INF;
	vector<int> ans;
	for (int i = l; i < r; i++){
		ll cur = 0;
		pair<ll, vector<int>> X, Y;
		int l1 = 0, r1 = k-1;
		while(l1 <= r1){
			int md = (l1+r1)/2;
			pair<ll, vector<int>> x, y;
			x = F(l, i, md);
			y = F(i+1, r, k-md-1);
			if (cur < x.ff+y.ff){
				cur = x.ff+y.ff;
				X = x; Y = y;
			}
			if (x.ff>y.ff) r1=md-1;
			else l1=md+1;
		}
		ll val = (pref[i]-pref[l-1])*(pref[r]-pref[i]);
		if (mx < cur+val){
			mx = cur+val; 
			ans.clear(); ans.pb(i);
			ans.insert(ans.end(), all(X.ss));
			ans.insert(ans.end(), all(Y.ss));
		}	
	}
	return {mx, ans};
}

int main ()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n >> k;
	for (int i = 1; i <= n; i++){
		cin >> a[i];
		pref[i] = pref[i-1]+a[i];	
	}
	for (int z = 1; z < n; z++){
		for (int i = 1; i <= n-z; i++){
			int l = i, r = i+z;
			for (int j = 1; j <= k; j++){
				int l2 = l, r2 = r-1;
				while(l2 <= r2){
					ll m = (l2+r2)/2;
					ll val = (pref[m]-pref[l-1])*(pref[r]-pref[m]), cur=0;
					pair<ll, vector<int>> X, Y;
					int l1 = 0, r1 = j-1;
					while(l1 <= r1){
						int md = (l1+r1)/2;
						pair<ll, vector<int>> x, y;
						x = dp[l][m][md];
						y = dp[m+1][r][j-md-1];
						if (cur < x.ff+y.ff){
							cur = x.ff+y.ff;
							X = x; Y = y;
						}
						if (x.ff>y.ff) r1=md-1;
						else l1=md+1;
					}
					vector<int> ans = {m};
					ans.insert(ans.end(), all(X.ss));
					ans.insert(ans.end(), all(Y.ss));
					dp[l][r][j] = max(dp[l][r][j], {cur+val, ans});
					if (pref[m]-pref[l-1]>pref[r]-pref[m]) r2=m-1;
					else l2=m+1;
				}
			}
		}
	}
	cout << dp[1][n][k].ff << '\n';
	for (auto i : dp[1][n][k].ss) cout << i << " ";
}	

Compilation message (stderr)

sequence.cpp: In function 'int main()':
sequence.cpp:89:25: warning: narrowing conversion of 'm' from 'long long int' to 'int' [-Wnarrowing]
   89 |      vector<int> ans = {m};
      |                         ^
sequence.cpp:89:25: warning: narrowing conversion of 'm' from 'long long int' to 'int' [-Wnarrowing]

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