Submission #1143488

#	Time	Username	Problem	Language	Result	Execution time	Memory
1143488		dpsaveslives	Hacker (BOI15_hac)	C++20	0 / 100	0 ms	328 KiB

hac

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 5e5+5;
int arr[MAXN],pref[MAXN];
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int N; cin >> N;
    for(int i = 1;i<=N;++i){
        cin >> arr[i];
        pref[i] = pref[i-1]+arr[i];
    }
    int len = (N+1)/2, ans = 0;
    set<int> s; map<int,int> cnt; //if it is 0, delete it
    for(int i = 1;i<=N;++i){
        if(s.size()){
            if(i-len-1 >= 0){
                --cnt[pref[i-1]-pref[i-len-1]];
                if(cnt[pref[i-1]-pref[i-len-1]] == 0){
                    s.erase(pref[i-1]-pref[i-len-1]);
                }
            }
        }
        if(i+len-1 <= N){
            s.insert(pref[i+len-1]-pref[i-1]);
            //cout << pref[i+len-1]-pref[i-1] << "\n";
            ++cnt[pref[i+len-1]-pref[i-1]];
        }
        else{
            s.insert(pref[N]-pref[i-1]+pref[len-(N-i+1)]);
            //cout << pref[N]-pref[i-1]+pref[len-(N-i+1)] << "\n";
            ++cnt[pref[N]-pref[i-1]+pref[len-(N-i+1)]];
        }
        ans = max(ans,(*s.begin()));
    }
    cout << ans << "\n";
    return 0;
}

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