/DAYSO4 - Dãy số (OLP Không chuyên 2008)

              Uses Crt;
        Var str:array[0..1000] of ansistring;
            digit_1,digit_2:ansistring;
            chr:char;
            n,i,j,count,remain:longint;
        Begin
            readln(n);
            str[0]:='0';
            for i:=1 to n do
             begin
                 str[i]:=''; digit_1:=''; digit_2:='';
                 remain:=0;
                 for chr:=str[i-1][1] to '9' do
                     if pos(chr,str[i-1])=0 then
                        begin
                           digit_1:=chr;
                           break;
                        end;
                 if  digit_1='' then
                  begin
                      for chr:='1' to '9' do
                       if pos(chr,str[i-1])=0 then
                        begin
                            digit_1:=chr;
                            break;
                        end;
                       remain:=remain+1;
                  end;
                 remain:=remain+length(str[i-1])-1;
                 for chr:='0' to '9' do
                  if pos(chr,str[i-1])=0 then
                   begin
                       for j:=1 to remain do digit_2:=digit_2+chr;
                       break;
                   end;
                 str[i]:=digit_1+digit_2;
                 //writeln(str[i]);
             end;
             writeln(str[n]);
             readln;
        End.
        (*Nhan xet
        Cac so chi co 2 chu so
        Co 2 van de la tim chu so dau tien va cac chu so dang sau deu giong nhau
        De tim chu so dau tien thi co hai truong hop: truong hop do dai cac so la bang nhau va truong hop do
                                                        dai cac so phai cong 1 
        *)