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 maxn = 1e6 + 10;
double a[maxn];
int main() {
  int n;
  scanf("%d", &n);
  double sum = 0;
  for (int i = 0; i < n; i++) {
    scanf("%lf", &a[i]);
    sum += a[i];
  }
  double av = sum * 1.0 / n;
  for (int i = 0; i < n; i++) {
    a[i] -= av;
  }
  double b = 0;
  double bb = 0;
  double Max = -1000000000.0;
  double Min = 1000000000.0;
  for (int i = 0; i < n; i++) {
    if (bb < 0) {
      bb += a[i];
    } else {
      bb = a[i];
    }
    if (b > 0) {
      b += a[i];
    } else {
      b = a[i];
    }
    Max = max(Max, b);
    Min = min(Min, bb);
  }
  printf("%.10lf\n", max(fabs(Max), fabs(Min)));
  return 0;
}
