#include <iostream>
#include <stack>
#include <string>
#include <queue>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <cassert>
using namespace std;
typedef long long ll;
double A[200002];
int N;
double solve(int i)
{
double l, r;
l = A[i];
r = A[i];
int s = i, e = i;
double now = A[i];
for(int i=1;i<N;i++)
{
double S = (now * i + A[s-1]) / (i + 1);
double E = (now * i + A[e+1]) / (i + 1);
if(s == 1)
{
now = E;
e++;
}
else if(e == N)
{
now = S;
s--;
}
else if(max(r, S) - min(l, S) <= max(r, E) - min(l, E))
{
now = S;
s--;
}
else
{
now = E;
e++;
}
r = max(r, now);
l = min(l, now);
}
return r - l;
}
int main()
{
ios::sync_with_stdio(false); cin.tie(NULL);
cin >> N;
for(int i=1;i<=N;i++) cin >> A[i];
double now = 0;
for(int i=1;i<=N;i++) now += A[i];
now /= N;
double ans = A[N] - A[1];
for(int i=1;i<=N;i++) ans = min(ans, solve(i));
cout.precision(15);
cout << ans;
}
