acwing 122

#include <bits/stdc++.h>
#define IOS ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define _zero(a) memset(a, 0, sizeof(a))
#define endl '\n'
#define int long long
#define mp make_pair
#define PII pair<int, int>
#define x first
#define y second
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define PII pair<int, int>
typedef long long ll;
typedef double dd;
typedef long double ld;

using namespace std;

const int inf = 1e10;
const int M = 998244353;
const ld pi = atan2(0, -1);//arctan(y/x);
const ld eps = 1e-8;

const int maxn = 1e6 + 100;
int a[maxn], f[maxn];
int sum[maxn];
int n;

bool cmp(int a1, int a2)
{
    return sum[a1] < sum[a2];
}

signed main()
{
    IOS;
    cin >> n;
    int avg = 0;
    for(int i = 1; i <= n; i++) {cin >> a[i]; avg += a[i]; f[i] = i;}
    avg /= n;
    for(int i = 1; i <= n; i++) a[i] -= avg;
    sum[0] = 0;
    for(int i = 1; i <= n; i++) sum[i] = sum[i-1] + a[i];
    sort(f + 1, f + 1 + n, cmp);
    int k = 0;
    if(n % 2) k = f[(n + 1) >> 1];
    else k = f[n >> 1];
    int ans = 0;
    for(int i = 1; i <= n; i++){
        ans += abs(sum[i] - sum[k]);
    }
    cout << ans << endl;
    return 0;
}