var k,suma,n,d,rez,ct,i:longint;
    fi,fo:text;
function putere(n,p:longint):longint;
begin
     k:=1;
     while k<=n do
        begin
             k:=k*p;
             suma:=suma+(n div k);
        end;
     putere:=suma;
     suma:=0;
end;
begin
     assign(fi,'pascal.in'); reset(fi);
     assign(fo,'pascal.out'); rewrite(fo);
     read(fi,n,d);
     ct:=0;
     for i:=1 to n-1 do begin
     rez:=putere(n,d)-putere(n-i,d)-putere(i,d);
     if rez>=1 then inc(ct); end;
     writeln(fo,ct);
     close(fi);
     close(fo);
end.