Submission #1139280

#	Time	Username	Problem	Language	Result	Execution time	Memory
1139280		buzdi	Hacker (BOI15_hac)	C++17	40 / 100	1092 ms	1860 KiB

hac

#include <bits/stdc++.h>

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
#define ll long long
#define ld long double

using namespace std;
using namespace __gnu_pbds;

typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

const int NMAX = 5e5;
const int INF = 2e9;

int n, k;
int s, max_answer;
int answer[NMAX + 1];
int a[2 * NMAX + 1];
int sp[2 * NMAX + 1];

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n;
    for(int i = 1; i <= n; i++) {
        cin >> a[i];
        a[n + i] = a[i];
    }
    k = n / 2 + n % 2;

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

    for(int i = 1; i <= n; i++) {
        answer[i] = INF;
    }

    for(int i = k; i - k + 1 <= n; i++) {
        int s_here = sp[i] - sp[i - k];
        for(int j = i - k + 1; j <= i; j++) {
            int pos = (j > n ? j - n : j);
            answer[pos] = min(answer[pos], s_here);
        }
    }

    for(int i = 1; i <= n; i++) {
        max_answer = max(max_answer, answer[i]);
    }
    cout << max_answer << '\n';

    return 0;
}

/*
    1 2 3 4 5 1 2 3 4 5
*/

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 40