var x:array[-1000000..1000000]of longint;i,m,f,j,c,l,g:longint;a,s,b,z:string;
Begin
        readln(a);
        read(b);
        if length(b)<length(a) then
        for i:=1 to length(a)-length(b) do
        b:='0'+b;
         if (length(a)<length(b))or(b>a)then begin
         z:=a;
         a:=b;b:=z;
         g:=1;
         end;
         if length(b)<length(a) then
        for i:=1 to length(a)-length(b) do
        b:='0'+b;

        for j:=length(a) downto 1 do
        begin
                        val(a[j],m,f); val(b[j],c,f);
                        x[j]:=x[j]+(m-c);

                        if x[j]<0 then begin
                        x[j]:=x[j]+10;
                        x[j-1]:=x[j-1]-1;
                        end;
        end;
           b:='';
        if g=1 then write('-');
        for i:=1 to length(a) do
        begin
        str(x[i],s);
        b:=b+s;
        end;
        while (b[1]='0')and(length(b)>1) do
        delete(b,1,1);
        writeln(b);
End.