#include<bits/stdc++.h>
using namespace std;

long long int numbr[200000];
int main()
{
    long long int i,j,k,num,cas=1;
    while(cin>>num && num)
    {
        for(i=0;i<num;i++)
            cin>>numbr[i];
        long long int suru,sesh,len,flag=0,pos;
        string s1,s2;
         cout<<"Case "<<cas++<<":"<<endl;
        for(i=0;i<num;i++)
        {
            if(numbr[i]+1 == numbr[i+1])
            {
                suru=i;
                j=i;
                while(numbr[j]+1 == numbr[j+1])
                {
                    j++;
                }
                sesh=j;
                cout<<"0"<<numbr[suru]<<"-";
                s1=to_string(numbr[suru]);
                s2=to_string(numbr[sesh]);
                flag=0;
                for(k=0;k<s2.length();k++)
                {
                    if(s1[k]!=s2[k])
                    {
                        pos=k;
                        break;
                    }
                }
               // cout<<"Pos "<<pos<<endl;
                for(k=pos;k<s2.length();k++)
                    cout<<s2[k];
                cout<<endl;
                i=j;
            }
            else
            {
                cout<<"0"<<numbr[i]<<endl;
            }
        }
        cout<<endl;
    }
    return 0;
}