Submission #1166976

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166976		belgianbot	Hacker (BOI15_hac)	C++20	100 / 100	218 ms	18176 KiB

hac

/*
    AUTHOR : BELGIANBOT
*/

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

template<typename T> void read(T& x) { cin >> x;}
template<typename T1, typename T2> void read(pair<T1, T2>& p) { read(p.first), read(p.second);}
template<typename T> void read(vector<T>& v) { for (auto& x : v) read(x); }
template<typename T1, typename T2> void read(T1& x, T2& y) { read(x), read(y); }
template<typename T1, typename T2, typename T3> void read(T1& x, T2& y, T3& z) { read(x), read(y), read(z); }
template<typename T1, typename T2, typename T3, typename T4> void read(T1& x, T2& y, T3& z, T4& zz) { read(x), read(y), read(z), read(zz); }
template<typename T> void print(vector<T>& v) { for (auto& x : v) cout << x << ' '; cout << endl; }

#define quit(x) return (void)(cout << x << endl)
#define pb push_back
#define fi first
#define se second
#define ordered_set tree<pair<int,int>, null_type, less<pair<int,int>>, rb_tree_tag, tree_order_statistics_node_update>
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define mp make_pair
#define sz(x) (int)(x.size())
#define YES cout<<"YES\n"
#define NO cout<<"NO\n"
#define QYES quit("YES")
#define QNO quit("NO")
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)
#define int long long
#define double long double


const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=20;

void solve();

signed main() {
   ios::sync_with_stdio(false);
   cin.tie(0);
   int t = 1;
   //cin >> t;
   while (t--) solve();
   return 0;
}

int k, n, m, p, q;
vector<vector<int>> adj;

void solve() {
    cin >> n;
    int mid = (n+1)/2;
    vector<int> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];

    int sum = 0;
    for (int i = 0; i < mid; i++) sum += a[i];

    multiset<int> st; st.insert(sum);
    deque<int> q; q.push_back(sum);
    for (int i = 0; i < mid-1; i++) {
        sum -= a[i]; sum += a[( mid+i)%n];
        st.insert(sum);
        q.push_front(sum);
    }
    int ans = 0;
    for (int i = 0; i <= n; i++) {
        ans = max(ans, *st.begin());
        int x = q.back(); q.pop_back();
        st.erase(st.find(x));
        sum -= a[(mid-1+i)%n]; sum += a[(mid*2+i-1)%n];
        st.insert(sum);
        q.push_front(sum);
    }
    cout << ans << '\n';
}

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