var a,b:array[0..30010]of longint;
    n,x,y,i,j:longint;
    max:real;

begin
     assign(input,'secv3.in');
     reset(input);
     assign(output,'secv3.out');
     rewrite(output);
     readln(n,x,y);
     for i:=1 to n do
     begin
          read(a[i]);
          a[i]:=a[i-1]+a[i];
     end;
     for i:=1 to n do
     begin
          read(b[i]);
          b[i]:=b[i-1]+b[i];
     end;
     max:=0;
     for i:=1 to n do
     begin
          for j:=i-x downto i-y do
          begin
               if j<0 then break;
               if max<(a[i]-a[j])/(b[i]-b[j]) then max:=(a[i]-a[j])/(b[i]-b[j]);
          end;
     end;
     writeln(max:0:2);
close(output);
end.