#include<bits/stdc++.h>
#define Woody
#define int long long
#define lowbit(x) (x&-x)
#define rep(n) for(int i=0;i<n;i++)
#define mp make_pair
#define eb emplace_back
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define SETIO(s) ifstream cin(s+".in");ofstream cout(s+".out");
#ifdef Woody
#define quick ios::sync_with_stdio(0);cin.tie(0);
#else
#define quick
#endif
#define INF INT64_MAX
using namespace std;
typedef pair<int,int> pii;
struct BIT{
    int n;
    vector<int> bit;
    void init(int l){
        n=l;
        bit.assign(n+1,0);
    }
    void add(int x,int val){
        for(int i=x;i<=n;i+=lowbit(i)){
            bit[i]+=val;
        }
    }
    int query(int x){
        int sum=0;
        for(int i=x;i>0;i-=lowbit(i)) sum+=bit[i];
        return sum;
    }
}tree;
signed main(){
    quick
    int n;
    int c=0;
    while(cin>>n&&n)
    {
        vector<int> v(n);
        vector<int>v2;
        rep(n) cin>>v[i],v2.eb(v[i]);
        sort(all(v2));
        v2.erase(unique(all(v2)),v2.end());
        int l=v2.size();
        tree.init(l);
        int ans=0;
        rep(n){
            int k=lower_bound(all(v2),v[i])-v2.begin()+1;
            ans+=tree.query(l)-tree.query(k);
            tree.add(k,1);
        }
        cout<<"Case #"<<++c<<": "<<ans<<"\n";
    }

}