type vector=array[0..1000000] of byte;
var a,b:vector;
    n,r,rest:int64;
    d:longint;
    f,g:text;
procedure p(var a:vector; n:int64);
var i:longint;
begin
     i:=1;
     while n>0 do
        begin
        a[i]:=n mod 10;
        n:=n div 10;
        inc(i);
        end;
     a[0]:=i-1;
end;
function modulo(a:vector;b:longint):int64;
var t:int64;
    i:longint;
begin
        t:=0;
        for i:=a[0] downto 1 do
                t:=(t * 10+a[i])mod b;
        modulo:=t;
end;
BEGIN
   assign(f,'next.in'); reset(f);
   assign(g,'next.out'); rewrite(g);
   readln(f,n);
   readln(f,d);
   p(b,n);
   r:=modulo(b,d);
   p(b,d-r);
   r:=modulo(b,d);
   writeln(g,n+r);
   close(f); close(g);
END.