#include<bits/stdc++.h>
#define int long long
#define ld double
#define _1 first
#define _2 second
#define yes cout<<"Yes\n"
#define nah cout<<"No\n"
#define FFF ios_base::sync_with_stdio(0);cin.tie(0);
#define ipr pair<int,int>
#define ret return
#define intt int32_t
#define mid ((l+r)/2)
#define pb push_back
#define lll __int128
using namespace std;
int tst, ts;
intt mo = 998244353, dx[] = {0, 1, 0, -1}, dy[] = {-1, 0, 1, 0};
int mul( int x, int y ) {
ret ( ( x % mo ) * ( y % mo ) ) % mo;
ret x*y;
}
int pwo( int x, int y ) {
int res = 1;
for( int i = 63; i + 1; i-- )
res = mul( res, res * ( ( 1ll << i )&y ? x : 1 ) );
ret res;
}
int dvii( int x, int y ) {
ret mul( x, pwo( y, mo - 2 ) );
}
int oo( char x ) {
ret ( int )x - '0';
}
int lgg( int x, int y ) {
int u = 0;
while( x ) {
u++;
x /= y;
}
ret u;
}
int mun( int x, int y ) {
while( x < y )x += mo;
ret ( x - y ) % mo;
}
int add( int x, int y ) {
ret x + y - ( mo * ( x + y >= mo ) );
ret x + y;
}
int lcm( int x, int y ) {
ret ( x * y ) / __gcd( x, y );
}
#define endl '\n';
const int M =2007, N = 2e5+ 7, N2 = 5e3 + 7, inf = 2e18+7 ;
double n,a[N],s,k;
struct ooo{
double an,mx,mn;
int o;
}dp[M][M];
void sol(int l, int r,double su){
if(dp[l][r].o)
ret;
if(l==r){
dp[l][r].mx=max(s,a[l]),dp[l][r].mn=min(s,a[l]);
dp[l][r].an=dp[l][r].mx-dp[l][r].mn;
ret;
}
sol(l+1,r,su-a[l]),sol(l,r-1,su-a[r]);
ooo u,p;
su/=(r-l+1);
u.mn=min(su,dp[l+1][r].mn);
u.mx=max(su,dp[l+1][r].mx);
u.an=u.mx-u.mn;
p.mn=min(su,dp[l][r-1].mn);
p.mx=max(su,dp[l][r-1].mx);
p.an=p.mx-p.mn;
if(p.an<u.an)
dp[l][r]=p;
else
dp[l][r]=u;
dp[l][r].o=1;
}
void solve(){
cin>>n;
double p=0;
s=0;
for(int i=0;i<n;i++){
cin>>a[i];
s+=a[i];
}
p=s;s/=n;
sol(0,n-1,p);
cout<<fixed<<setprecision(10);
cout<<dp[0][(int )n-1].an+0.0000000001<<endl;
}
intt main() {
FFF
//freopen("fcolor.in", "r", stdin);
//freopen("fcolor.out", "w", stdout);
tst = 1;
//cin >> tst;
for ( ts = 1; ts <= tst; ts++ ){
solve();
}
}
