Submission #1171605

#	Time	Username	Problem	Language	Result	Execution time	Memory
1171605		PieArmy	Lightning Conductor (POI11_pio)	C++20	100 / 100	64 ms	21064 KiB

pio

#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
#define int ll
int n;
int arr[500023],pref[500023],ans[500023],spec[500023];

ll kes(int a,int b){
	ll x=arr[a]-arr[b];
	ll y=(a-b-(x*x)-1ll)/ll(2*x);
	return a+max(0ll,min(ll(n-a),y<0?-1ll:(y*y)));
}

void f(){
	for(int i=1;i<=n;i++){
		pref[i]=pref[i-1];
		spec[i]=0;
		if(arr[i]>arr[pref[i]])pref[i]=i;
	}
	int pos=pref[n-1];
	while(pos){
		spec[pos]=1;
		pos=pref[pos-1];
	}
	deque<int>q;
	for(int i=1;i<=n;i++){
		while(q.size()>1){
			if(kes(q[1],q[0])<i)q.pop_front();
			else break;
		}
		if(q.size())ans[i]=max(ans[i],arr[q[0]]+int(sqrt(i-q[0]-1))+1-arr[i]);
		if(spec[i]){
			while(q.size()>1){
				int a=q.back();q.pop_back();
				if(kes(a,q.back())>=kes(i,q.back()))continue;
				q.push_back(a);
				break;
			}
			q.push_back(i);
		}
	}
}

int32_t main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);
	cin>>n;
	arr[0]=-1;
	for(int i=1;i<=n;i++){
		cin>>arr[i];
	}
	if(n==1){
		cout<<0;
		return 0;
	}
	f();
	reverse(arr+1,arr+n+1);
	reverse(ans+1,ans+n+1);
	f();
	for(int i=n;i>=1;i--){
		cout<<ans[i]<<"\n";
	}
}

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 9 / 9
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 10 / 10