program secventa3;
var f,g:text;
        n,l,u:longint;
        s,t:array[0..30001] of real;



procedure iofile;
var i:longint;
begin
        fillchar(s,sizeof(s),0);
        fillchar(t,sizeof(t),0);
        assign(f,'secv3.in');
        reset(f);
        assign(g,'secv3.out');
        rewrite(g);
        readln(f,n,l,u);
        read(f,s[1]);
        for i:=2 to n do
                begin
                        read(f,s[i]);
                        s[i]:=s[i]+s[i-1];
                end;
        readln(f);
        read(f,t[1]);
        for i:=2 to n do
                begin
                        read(f,t[i]);
                        t[i]:=t[i]+t[i-1];
                end;
        close(f);
end;



procedure prel;
var i,j:longint;
        max:real;
begin
        max:=-1;
        for i:=1 to n-l+1 do
                for j:=i+l-1 to i+u-1 do
                        if (s[j]-s[i-1])/(t[j]-t[i-1])>max then
                                max:=(s[j]-s[i-1])/(t[j]-t[i-1]);
        writeln(g,max:0:2);
        close(g);
end;


begin
        iofile;
        prel;
end.