program natjecanje;
var n, s, r : shortint;
    vr      : array[0..11] of shortint;
    i, j    : integer;
    wbatp   : shortint;

begin
    readln(n, s, r);
    for i := 0 to 11 do
        vr[i] := 0;
    for i := 1 to s do begin
        read(j);
        vr[j] := 1;
    end;
    for i := 1 to r do begin
        read(j);
        if vr[j] = 1 then vr[j] := 0
        else vr[j] := 2;
    end;
    for i := 1 to 10 do
        if vr[i] = 2 then
            if vr[i-1] = 1 then begin
                vr[i] := 0;
                vr[i-1] := 0;
            end
            else if vr[i+1] = 1 then begin
                vr[i] := 0;
                vr[i+1] := 0;
            end;
    wbatp := 0;
    for i := 1 to 10 do
       if vr[i] = 1 then
           inc(wbatp);
    writeln(wbatp);
end.