1 #include <cmath>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <algorithm>
 5 #define N1 105
 6 #define M1 50010
 7 #define ll long long
 8 #define dd double
 9 #define inf 0x3f3f3f3f
10 using namespace std;
11
12 int gint()
13 {
14     int ret=0,fh=1;char c=getchar();
15     while(c<'0'||c>'9'){if(c=='-')fh=-1;c=getchar();}
16     while(c>='0'&&c<='9'){ret=ret*10+c-'0';c=getchar();}
17     return ret*fh;
18 }
19
20 int n,m,S,T;
21 struct Edge{
22 int head[N1],to[M1<<1],nxt[M1<<1],dis[M1<<1],flow[M1<<1],cte;
23 void ae(int u,int v,int F,int W)
24 {
25     cte++; to[cte]=v; flow[cte]=F; dis[cte]=W;
26     nxt[cte]=head[u]; head[u]=cte;
27 }
28 }e;
29
30 int que[M1<<1],dis[N1],flow[N1],use[N1],id[N1],hd,tl;
31 int spfa()
32 {
33     int x,j,v;
34     memset(dis,0x3f,sizeof(dis)); memset(use,0,sizeof(use)); memset(flow,0,sizeof(flow));
35     hd=1,tl=0; que[++tl]=S; dis[S]=0; flow[S]=inf; use[S]=1;
36     while(hd<=tl)
37     {
38         x=que[hd++];
39         for(j=e.head[x];j;j=e.nxt[j])
40         {
41             v=e.to[j];
42             if( e.flow[j]>0 && dis[v]>dis[x]+e.dis[j] )
43             {
44                 dis[v]=dis[x]+e.dis[j]; id[v]=j;
45                 flow[v]=min(flow[x],e.flow[j]);
46                 if(!use[v]) que[++tl]=v, use[v]=1;
47             }
48         }
49         use[x]=0;
50     }
51     return dis[T]!=inf;
52 }
53
54 int mxflow,cost;
55 int EK()
56 {
57     int x;
58     while(spfa())
59     {
60         for(x=T;x!=S;x=e.to[id[x]^1])
61         {
62             e.flow[id[x]]-=flow[T];
63             e.flow[id[x]^1]+=flow[T];
64         }
65         mxflow+=flow[T]; cost+=flow[T]*dis[T];
66     }
67     return cost;
68 }
69
70 int a[N1];
71
72 int main()
73 {
74     scanf("%d",&n);
75     int i,x,y,z,sum=0; e.cte=1; S=n+1,T=n+2;
76     for(i=1;i<=n;i++) scanf("%d",&a[i]), sum+=a[i]; sum/=n;
77     for(i=1;i<=n;i++)
78         if(a[i]>sum) e.ae(S,i,a[i]-sum,0), e.ae(i,S,0,0);
79         else if(a[i]<sum) e.ae(i,T,sum-a[i],0), e.ae(T,i,0,0);
80     for(i=1;i<n;i++) e.ae(i,i+1,inf,1), e.ae(i+1,i,0,-1); e.ae(n,1,inf,1), e.ae(1,n,0,-1);
81     for(i=2;i<=n;i++) e.ae(i,i-1,inf,1), e.ae(i-1,i,0,-1); e.ae(1,n,inf,1), e.ae(n,1,0,-1);
82     printf("%d\n",EK());
83     //for(i=1,num=0;i<=n;i++) num+=abs(a[i]-sum);
84     return 0;
85 }