#include <vector>
using namespace std;
typedef long long int ll;
#define ull unsigned long long
#define rep(i, m, n) for (auto i = m; i < n; i++)
#define mi map<ll,ll>::iterator
#define pb push_back
#define pob pop_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define MOD 1000000007
#define f(n) for(int i=0;i<n;i++)
#define PI 3.1415926536
#define dhroov ios_base::sync_with_stdio(false); cin.tie(NULL);
#define taxi auto
// ll visited[51][51];
// #define N=100001;
// bool visited[N];
// DFS
ll dfs(ll z,ll c, ll i, ll j,vector<vector<ll>> a,ll (&visited)[51][51])
{
if(i>=z||i<0||j>=c||j<0||visited[i][j]!=0) return 0;
visited[i][j]=1;
ll p,q,r,s,t,u,v,w;
p=q=r=s=t=u=v=w=0;
if(i+1<a.size()&&a[i+1][j]==a[i][j]+1){p=1; p+=dfs(z,c,i+1,j,a,visited);}
if(j+1<a[0].size()&&a[i][j+1]==a[i][j]+1){ q=1; q+=dfs(z,c,i,j+1,a,visited);}
if(i-1>=0&&a[i-1][j]==a[i][j]+1){ r=1; r+=dfs(z,c,i-1,j,a,visited);}
if(j-1>=0&&a[i][j-1]==a[i][j]+1){ s=1; s+=dfs(z,c,i,j-1,a,visited);}
if(i+1<a.size()&&j+1<a[0].size()&&a[i+1][j+1]==a[i][j]+1){ t=1; t+=dfs(z,c,i+1,j+1,a,visited);}
if(i+1<a.size()&&j-1>=0&&a[i+1][j-1]==a[i][j]+1){ u=1; u+=dfs(z,c,i+1,j-1,a,visited);}
if(i-1>=0&&j+1<a[0].size()&&a[i-1][j+1]==a[i][j]+1){ v=1; v+=dfs(z,c,i-1,j+1,a,visited);}
if(i-1>=0&&j-1>=0&&a[i-1][j-1]==a[i][j]+1){ w=1; w+=dfs(z,c,i-1,j-1,a,visited);}
return(max({p,q,r,s,t,u,v,w}));
}
int main()
{
dhroov;
ll t,y=0;
while(1)
{
ll visited[51][51]={0};
y++;
ll r,c,m,ans=0;
char z;
cin>>r>>c;
if(r==0&&c==0) break;
vector<vector<ll>> v;
f(r){vector <ll> k; rep(j,0,c) {cin>>z;k.pb(int(z)-65);}v.pb(k);}
// cin>>h>>w;
f(r)
{
rep(j,0,c)
{
// cout<<i<<j<<" ";
if(v[i][j]==0)
{
// cout<<i<<j<<" ";
m=dfs(r,c,i,j,v,visited);
// cout<<m<<" ";
// cout<<m<<endl;
ans=max(ans,m+1);
}
}
}
cout<<"Case :"<<y<<" "<<ans<<endl;
}
}
