Submission #676498

#	Time	Username	Problem	Language	Result	Execution time	Memory
676498		penguin133	Hacker (BOI15_hac)	C++17	100 / 100	59 ms	20404 KiB

hac

#include <bits/stdc++.h>
using namespace std;
#define int long long
int dp[1000005], B[1000005], P[1000005], S[500005];
deque<int>dq;
main(){
	ios::sync_with_stdio(0);cin.tie(0);
	int n;cin >> n;
	for(int i=1;i<=n;i++)cin >> B[i];
	for(int i=n+1;i<=n*2;i++)B[i] = B[i-n];
	for(int i=1;i<=2*n;i++)P[i] = P[i-1] + B[i];
	int x = n / 2;
	for(int i=1;i<=n-x;i++){
		while(!dq.empty() && P[dq.back() + x-1] - P[dq.back()-1] < P[i+x-1] - P[i-1])dq.pop_back();
		dq.push_back(i);
	}
	int maxi = 1e9;
	for(int i=1;i<=n;i++){
		while(!dq.empty() && P[dq.back() + x-1] - P[dq.back()-1] < P[n+i-1] - P[n+i-x-1])dq.pop_back();
		if(!dq.empty() && dq.front() == i)dq.pop_front();
		dq.push_back(n+i-x);
		maxi = min(maxi, P[dq[0] + x - 1] - P[dq[0] - 1]);
	}
	cout << P[n] - maxi;
}

Compilation message (stderr)

hac.cpp:6:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
    6 | main(){
      | ^~~~

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