Submission #479632

#	Time	Username	Problem	Language	Result	Execution time	Memory
479632		Lobo	Hacker (BOI15_hac)	C++17	100 / 100	138 ms	22752 KiB

hac

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

const long long INFll = (long long) 1e18 + 10;
const int INFii = (int) 1e9 + 10;
typedef long long ll;
typedef int ii;
typedef long double dbl;
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()

#define maxn 1050000

ii n, v[maxn], r[maxn], ps[maxn]; 

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

    //freopen("in.in", "r", stdin);
    //freopen("out.out", "w", stdout);

    cin >> n;

    for(ii i = 1; i <= n; i++) {
        cin >> v[i];
        v[i+n] = v[i];
    }

    for(ii i = 1; i <= 2*n; i++) {
        ps[i] = ps[i-1] + v[i];
        r[i] = INFii;
    }

    ii ans = 0;
    ii sz = (n+1)/2;
    //cout << sz << endl;

    priority_queue<pair<ii,ii>> pq;

    for(ii i = 1; i <= 2*n; i++) {
        if(i+sz-1 <= 2*n) pq.push(mp(-(ps[i+sz-1]-ps[i-1]),i));

        while(pq.size() && pq.top().sc <= i-sz) pq.pop();
        r[i] = -pq.top().fr;

    }

    for(ii i = 1; i <= n; i++) {
        ans = max(ans, min(r[i],r[i+n]));
        //cout << i << " " << min(r[i],r[i+n]) << endl;
    }

    cout << ans << endl;



}

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