var d:int64;
    n:char;
    a,b,c:array[0..10000000] of longint;
    m,er,t,k,j,i,aux:longint;
    f,g:text;
begin
assign(f,'next.in');
assign(g,'next.out');
reset(f);
rewrite(g);
while not eoln(f) do begin
read(f,n);
a[0]:=a[0]+1;
val(n,a[a[0]]);
end;
readln(f);
readln(f,d);
for i:=1 to a[0] div 2 do begin
                        aux:=a[i];
                        a[i]:=a[a[0]-i+1];
                        a[a[0]-i+1]:=aux;
                        end;
for i:=0 to a[0] do c[i]:=a[i];
t:=0;
i:=a[0];;
while i>0 do begin
                t:=t*10+a[i];
                a[i]:=t div d;
                t:=t mod d;
                i:=i-1;
             end;
while (a[0]>0) and (a[a[0]]=0) do a[0]:=a[0]-1;
d:=d-t;
repeat
k:=k+1;
b[k]:=d mod 10;
d:=d div 10;
until d=0;
t:=0;
i:=1;
while (i<=c[0]) or (i<=b[0]) or (t>0) do
        begin
        t:=t+c[i]+b[i];
        c[i]:=t mod 10;
        t:=t div 10;
        i:=i+1;
        end;
c[0]:=i-1;
for i:=c[0] downto 1 do write(g,c[i]);
close(f);
close(g);
end.
var d,t:int64;
    n:char;
    a,b,c:array[0..100000000] of integer;
    m,er,k,j,i,aux:longint;
    f,g:text;
begin
assign(f,'next.in');
assign(g,'next.out');
reset(f);
rewrite(g);
while not eoln(f) do begin
read(f,n);
a[0]:=a[0]+1;
val(n,a[a[0]]);
end;
readln(f);
readln(f,d);
for i:=1 to a[0] div 2 do begin
                        aux:=a[i];
                        a[i]:=a[a[0]-i+1];
                        a[a[0]-i+1]:=aux;
                        end;
for i:=0 to a[0] do c[i]:=a[i];
t:=0;
i:=a[0];;
while i>0 do begin
                t:=t*10+a[i];
                a[i]:=t div d;
                t:=t mod d;
                i:=i-1;
             end;
while (a[0]>0) and (a[a[0]]=0) do a[0]:=a[0]-1;
d:=d-t;
repeat
k:=k+1;
b[k]:=d mod 10;
d:=d div 10;
until d=0;
t:=0;
i:=1;
while (i<=c[0]) or (i<=b[0]) or (t>0) do
        begin
        t:=t+c[i]+b[i];
        c[i]:=t mod 10;
        t:=t div 10;
        i:=i+1;
        end;
c[0]:=i-1;
for i:=c[0] downto 1 do write(g,c[i]);
close(f);
close(g);
end.