var
  n, i, j, k, t, j2, l, s : integer;
  slovo : string;

  vstup, vystup : array[1..11000] of char;






begin

  readln(n);
  while n <> 0 do begin
    k := 0;
    i := 0;
    read(slovo);
    k := k + length(slovo);
    while slovo <> '' do begin


      
      for j := 1 to length(slovo) do begin

          vstup[i * 255 + j] := slovo[j];

      end;

      //writeln('-----------------');
      //writeln(n, ' - ', slovo);
      //writeln(vstup);

      inc(i);

      read(slovo);
      k := k + length(slovo);
    end;

    //writeln(vstup);


    j2 := 0;
    l := k;
    
    for j := 1 to l do begin
      if vstup[j] <> ' ' then begin
        inc(j2);

        vstup[j2] := vstup[j]; 
      end;
    end;

    //writeln(vstup);

    k := j2;

    vystup := '';

    t := 1;
    s := 1;
    for j := 1 to k do begin




      vystup[t] := upcase(vstup[j]);

       t := t + n;

       if t > k then begin
         s := s + 1;
         t := s;
       end;

    end;




    write(vystup);
    //write('*');
    writeln;



    //vstup : ='';
    //vystup := '';


    readln;
    readln(n);
  end;












end.