#pragma GCC optimize("O3")
#pragma GCC target("avx")
#include <stdio.h>
// #include <vector>
#include <bits/stdc++.h>

using namespace std;
#define int long long
#define REP(i, n) for (int i = 0; i < (n); i++)
int scan() {
  auto minus = false;
  int result = 0;
  while (true) {
    auto k = getchar_unlocked();
    if (k == '-')
      minus = true;
    else if (k < '0' || k > '9')
      break;
    else
      result = 10 * result + k - '0';
  }
  return result * (minus ? -1 : 1);
}
int get_median(int* A, int start, int end) {
  if (end - start < 32) {
    nth_element(A + start, A + (start + end) / 2, A + end);
    return A[(start + end) / 2];
  }
  int l = (end - start) / 5;
  int ls[] = {
      get_median(A, start, start + l),
      get_median(A, start + l, start + 2 * l),
      get_median(A, start + 2 * l, start + 3 * l),
      get_median(A, start + 3 * l, start + 4 * l),
      get_median(A, start + 4 * l, end),
  };
  nth_element(ls, ls + 2, ls + 5);
  return ls[2];
}

int Y[1000010];
signed main() {
  int n = scan();
  REP(i, n) Y[i] = scan();
  int mid = get_median(Y, 0, n);
  // sort(Y, Y + n);
  // nth_element(Y, Y + n / 2, Y + n);  // n/2までソートで足りる
  // int mid = Y[n / 2];
  int ans = 0;
  REP(i, n) ans += abs(Y[i] - mid);
  printf("%lld\n", ans);
}