Submission #1114705

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114705		Thunnus	Hacker (BOI15_hac)	C++17	100 / 100	325 ms	26312 KiB

hac

#include<bits/stdc++.h>
using namespace std;
using i64 = long long;
#define int i64
#define vi vector<int>
#define vvi vector<vi>
#define vb vector<bool>
#define pii pair<int, int>
#define fi first
#define se second
#define sz(x) (int)(x).size()

signed main(){
    ios_base::sync_with_stdio(false); cin.tie(0);
    int n;
    cin >> n;
    const int SZ = (n + 1) / 2;
    vi a(2 * n + 1);
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        a[n + i] = a[i];
    }
    for(int i = 1; i <= 2 * n; i++){
        a[i] += a[i - 1];
    }
    
    auto sum = [&](int l, int r) -> int  {
        if(!l) return a[r];
        return a[r] - a[l - 1];
    };

    multiset<int> s;
    vi ans(n + 1, LLONG_MAX);
    for(int i = 1; i <= 2 * n; i++){
        if(i + SZ - 1 <= 2 * n) s.emplace(sum(i, i + SZ - 1));
        if(i > SZ) s.erase(s.find(sum(i - SZ, i - 1)));
        ans[(i - 1) % n + 1] = min(ans[(i - 1) % n + 1], *s.begin());
    }
    cout << *max_element(ans.begin() + 1, ans.end()) << "\n";
    return 0;
}

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