Submission #884632

#	Time	Username	Problem	Language	Result	Execution time	Memory
884632		MisterReaper	Hacker (BOI15_hac)	C++17	100 / 100	261 ms	24420 KiB

hac

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;

const int INF = 1E9;

#define ONLINE_JUDGE
void solve() {
    int n;
    cin >> n;

    vector <int> a(2 * n +1);
    for(int i = 1; i <= n; i++) {
        cin >> a[i];
        a[i + n] = a[i];
    }

    vector <int> pref = a;
    for(int i = 1; i <= 2 * n; i++) {
        pref[i] += pref[i -1];
    }

    auto get = [&](int x, int y) -> int {
        return pref[x] - pref[y -1];
    };

    vector <int> ans(n, INF);
    int sz = (n +1) / 2;
    multiset <int> ms;
    for(int i = 1; i <= 2 * n; i++) {
        if(i + sz -1 <= 2 * n) {
            ms.emplace(get(i + sz -1, i));
        }
        if(i - sz >= 1) {
            ms.erase(ms.find(get(i -1, i - sz)));
        }

        /*
        cerr << i << ":\n";
        for(const int &j : ms) {
            cerr << j << " ";
        }
        cerr << "\n";
        */
        
        ans[i % n] = min(ans[i % n], *ms.begin());
    }

    cout << *max_element(ans.begin(), ans.end());
    
    return;
}

signed main() {
    #ifndef ONLINE_JUDGE
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
    #endif

    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

    int t = 1; //cin >> t;
    for(int i = 1; i <= t; i++) {
        solve();
    }

    return 0;
}

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