//
// Created by adavy on 5/11/2025.
//
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = long double;
int N; vector<db> nums, numprefs;
const db EPS = 1e-9;
db incl_sum(int l, int r){
if (l > r) return 0;
return numprefs[r+1] - numprefs[l];
}
bool is_good(db len){
for(int l=0;l<N;++l) for(int r=l; r <= N;++r){
int num_terms = r-l;
db sm = incl_sum(0, N-1) - incl_sum(0, l-1) - incl_sum(r, N-1);
db lb = sm/(num_terms);
db rb = lb + len;
db cursum = incl_sum(0, N-1);
db start = incl_sum(0, N-1)/N;
db curterms = N;
if(!(lb <= start && start <= rb)){
continue;
}
int lptr = 0, rptr = N-1;
while(lptr < rptr){
db lsum = cursum - incl_sum(lptr, lptr);
db rsum = cursum - incl_sum(rptr, rptr);
if (lb <= lsum/(curterms-1) && lsum/(curterms-1) <= rb){
lptr++;
curterms--;
cursum -= incl_sum(lptr-1, lptr-1);
} else if (lb <= rsum/(curterms-1) && rsum/(curterms-1) <= rb){
rptr--;
curterms--;
cursum -= incl_sum(rptr+1, rptr+1);
} else {
break;
}
}
if (lptr >= rptr){
return true;
}
}
return false;
}
int main(){
cin >> N;
nums.resize(N);
numprefs.resize(N+1, 0);
for(int i=0;i<N;++i){
cin >> nums[i];
numprefs[i+1] = numprefs[i] + nums[i];
}
db lo = 0, hi = 2e9;
while ((hi-lo) >= EPS){
if (is_good((hi+lo)/2)){
hi = (hi+lo)/2;
} else {
lo = (hi+lo)/2;
}
}
cout << fixed << setprecision(10) << hi << endl;
}
