{$A+,B-,D+,E+,F-,G-,I+,L+,N-,O-,R+,S+,V+,X-}
{$M 16384,0,655360}
Var f:text;
    r,n,k,i,j,c,uf,se,ner,x:integer;
    fr,frer:array[1..34] of integer;
    st:array[1..34] of string;
    cd:array[1..34] of string;
    s:string;
    elso:boolean;

Function FStr(a:integer):string;
 var x:string;
 begin
      Str(a,x);
      FStr:=x;
 end;

Procedure Kiir;
 var os,fros:integer;
 begin
      Write('Set ',se,'; average length ');
      os:=0; fros:=0;
      For i:=1 To ner Do
          begin
          Inc(os,Length(cd[i])*frer[i]);
          Inc(fros,frer[i]);
          end;
      WriteLn(os/fros:1:2);
      For i:=1 To ner Do WriteLn('    ',Chr(i+64),': ',cd[i]);
      WriteLn;
      Inc(se);
 end;

Procedure Kodol;
 begin
      Repeat
      If elso Then x:=n Else x:=1;
      elso:=false;
      For i:=1 To x Do
          For j:=n-1 DownTo i Do
              If (fr[j]<fr[j+1]) or ((fr[j]=fr[j+1]) and (st[j]<st[j+1])) Then
                 begin
                 c:=fr[j]; fr[j]:=fr[j+1]; fr[j+1]:=c;
                 s:=st[j]; st[j]:=st[j+1]; st[j+1]:=s;
                 end;
      s:=''; uf:=0;
      For i:=n DownTo n-r+1 Do
          begin
          s:=st[i]+s;
          Inc(uf,fr[i]);
          For j:=1 To Length(st[i]) Do cd[Ord(st[i][j])]:=FStr(n-i)+cd[Ord(st[i][j])];
          end;
      Dec(n,r-1);
      st[n]:=s; fr[n]:=uf;
      Until n=1;
 end;

BEGIN
     se:=1;
     Assign(f,'coding.in');
     Reset(f);
     Repeat
           Read(f,r);
           If r>0 Then
              begin
              For i:=1 To 34 Do
                  begin
                  st[i]:=Chr(i);
                  cd[i]:='';
                  end;
              FillChar(fr,SizeOf(fr),0);
              Read(f,n);
              For k:=1 To n-1 Do
                  Read(f,fr[k]);
              ReadLn(f,fr[n]);
              ner:=n; frer:=fr;
              If n-r>=0 Then c:=(n-r) mod (r-1) Else c:=n-1;
              If c>0 Then Inc(n,r-1-c);
              elso:=true;
              Kodol;
              Kiir;
              end;
     Until r=0;
     Close(f);
END.