program slatkisi;
var s,c,k,d,x:integer;
    r,b,h:integer;

begin
     readln(c);
     readln(k);
     s:=1;
     for x:=1 to k do
         s:=s*10;
     d:=c mod s;
     r:=s div 2;
     if d<r then b:=c-d;
     if d>=r then
     begin
     h:=c-d;
     b:=h+s;
     end;
     if c<s then b:=s;
     writeln(b);
end.