10
-405 -230 252 -393 -390 -259 97 163 81 -129
 3
10000 -10000 10000
 1
-10000
 20
-16 -23 29 44 -40 -50 -41 34 -38 30 -12 28 -44 -49 15 50 -28 38 -2 0

702.333333333333712
 10000.000000000016371
 0.000000000000000
 113.875000000000043

#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 10, INF = 0x3f3f3f3f, MOD = 1e9 + 7;
int n;
double a[N];
int main() {
  ios_base::sync_with_stdio(0);
  while (scanf("%d", &n) == 1) {
    double x = 0;
    for (int i = 1; i <= n; ++i) {
      scanf("%lf", a + i);
      x += a[i];
    }
    x /= n;
    for (int i = 1; i <= n; ++i) a[i] -= x;
    double sum = 0, ans1 = 0, ans2 = 0;
    for (int i = 1; i <= n; ++i) {
      sum += a[i];
      if (sum > ans1) ans1 = sum;
      if (sum < 1e-10) sum = 0;
    }
    for (int i = 1; i <= n; ++i) a[i] = -a[i];
    for (int i = 1; i <= n; ++i) {
      sum += a[i];
      if (sum > ans2) ans2 = sum;
      if (sum < 1e-10) sum = 0;
    }
    printf("%.10f\n", min(ans1, ans2));
  }
  return 0;
}
