Submission #853536

#	Time	Username	Problem	Language	Result	Execution time	Memory
853536		NK_	Hacker (BOI15_hac)	C++17	100 / 100	234 ms	30012 KiB

hac

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
 
using namespace std;
 
#define nl '\n'
#define pb push_back
#define pf push_front
 
#define mp make_pair
#define f first
#define s second
#define sz(x) int(x.size())
 
template<class T> using V = vector<T>;
using pi = pair<int, int>;
using vi = V<int>;
using vpi = V<pi>;
 
using ll = long long;
using pl = pair<ll, ll>;
using vpl = V<pl>;
using vl = V<ll>;
 
using db = long double;
 
template<class T> using pq = priority_queue<T, V<T>, greater<T>>;
 
const int MOD = 1e9 + 7;
const ll INFL = ll(1e17);
const int LG = 18;

int main() {
	cin.tie(0)->sync_with_stdio(0);

	int N; cin >> N;
	vi A(N); for(auto& x : A) cin >> x;

	for(int i = 0; i < N; i++) A.pb(A[i]);

	vl P = {0}; for(int i = 0; i < 2*N; i++) P.pb(P.back() + A[i]);

	auto qry = [&](int l, int r) {
		return P[r+1] - P[l];
	};

	int M = (N + 1) / 2;

	vi S;
	for(int i = 0; (i+M-1) < 2*N; i++) S.pb(qry(i, i + M - 1));

	multiset<int> MN;

	int ans = 0;
	for(int i = 0; i < sz(S); i++) {
		MN.insert(S[i]);
		if (i-M >= 0) MN.erase(MN.find(S[i-M]));

		if (sz(MN) == M) ans = max(ans, *begin(MN));
	}

	cout << ans << nl;

	exit(0-0);
} 	

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 40 / 40