begin 
comment lib 1;
    procedure recursive(level, l);
        value 
            level;
        integer 
            level;
        label 
            l;
        begin 
        if level != 0 then 
            recursive(level - 1, exit)
        else 
            go to l;
       exit :;
        outreal(1,level)
        end;

    recursive(10, exit);
   exit :;
end