1 #include <bits/stdc++.h>
2 #define _for(i,a,b) for(int i = (a);i < (b);i ++)
3 #define pb push_back
4 #define is sizeof(int)
5
6 using namespace std;
7 const int maxn = 9;
8
9 int n;
10 int maxd;
11 int v[maxn];
12
13 int readint() {int tmp;scanf("%d",&tmp);return tmp;}
14 void read()
15 {
16 int vend = 0;
17 _for(i,0,n)
18 v[vend++] = readint();
19 }
20
21 int wnc()//wrong number count
22 {
23 int cnt = 0;
24 _for(i,1,n)
25 if(v[i-1]+1!=v[i])
26 cnt ++;
27 return cnt;
28 }
29
30 bool dfs(int d)
31 {
32 if(3*d+wnc()>3*maxd) return false;
33 if(wnc()==0) return true;
34 int vv[maxn];
35 memcpy(vv,v,sizeof(v));
36 int tmp[maxn];
37 _for(i,0,n)//confirm the beginning
38 {
39 if(i==0 || vv[i] != vv[i-1]+1)
40 {
41 _for(j,i,n)
42 {
43 while(j+1<n && vv[j+1]==vv[j]+1) j++;
44 memcpy(tmp,vv+i,is*(j-i+1));//move part
45 _for(k,j+1,n)
46 {
47 while(k+1<n && vv[k+1]==vv[k]+1) k++;
48 memcpy(v+i,vv+j+1,is*(k-j));
49 memcpy(v+i+(k-j),tmp,is*(j-i+1));
50 if(dfs(d+1))return true;
51 memcpy(v,vv,sizeof(v));
52 }
53 }
54 }
55 }
56 return false;
57 }
58
59 int solve()
60 {
61 if(wnc()==0) return 0;
62 for(maxd = 1; ;maxd ++)
63 {
64 if(dfs(0)) break;
65 }
66 return maxd;
67 }
68
69 int kase = 1;
70 void output(int rnt)
71 {
72 printf("Case %d: %d
",kase++,rnt);
73 }
74
75 int main()
76 {
77 while(~scanf("%d",&n)&&n!=0)
78 {
79 memset(v,0,sizeof(v));
80 read();
81 output(solve());
82 }
83 return 0;
84 }
