C++ :

#include<bits/stdc++.h>
using namespace std;
int n,a[1500000],ave;
long long c[1850000],tot;
int main()
{
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        scanf("%d",&a[i]);
        tot+=a[i];
    }
    ave=tot/n;
    for(int i=1;i<=n-1;i++)
        c[i]=c[i-1]+a[i]-ave;
        
    sort(c,c+n);
    int mid=(n-1)/2;
    long long ans=0;
    for(int i=0;i<=mid;++i)
        ans+=c[n-i-1]-c[i];

    printf("%lld",ans);
}

#include<bits/stdc++.h>
typedef long long LL;
const int INF = 0x3f3f3f3f;
const int N = 1e6+5;
LL n,a[N],b[N],x,s,ans;
using namespace std;
int main()
{
	cin>>n;
	for(int i=1;i<=n;++i){
		cin>>a[i];
		x+=a[i];
	}
	x/=n;
	for(int i=1;i<=n;++i)b[i]=b[i-1]+x-a[i-1];
	sort(b+1,b+n+1);
	s=b[(n+1)/2];
	for(int i=1;i<=n;++i)ans+=abs(s-b[i]);
	cout<<ans;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,a[1500000],ave;
long long c[1850000],tot;
int main()
{
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        scanf("%d",&a[i]);
        tot+=a[i];
    }
    ave=tot/n;
    for(int i=1;i<=n-1;i++)
        c[i]=c[i-1]+a[i]-ave;
        
    sort(c,c+n);
    int mid=(n-1)/2;
    long long ans=0;
    for(int i=0;i<=mid;++i)
        ans+=c[n-i-1]-c[i];

    printf("%lld",ans);
}