{輸入n,r  ; 從前n個自然數中取r個數作組合}
program combination
type  
    s=array [1..20] of integer;
var 
    s  a;
    integer n,r;
procedure  com(integer s,j);
var integer i,k;
begin
   i:=s;
   while i<n+2-j  do
     a[r+1-j]:=i;
     if j<2
     then  k:=1;
           while k<r+1 do
             write(a[k]);
             k:=k+1
           endwh
     else  com(i+1,j-1)
     fi;
     i:=i+1
   endwh
end
begin
read(n); {n為組合的界限}
read(r); {r為組合數}
com(1,r)
end.