import sequtils,strutils,strscans,algorithm,math,future,macros
import sets,tables,intsets
template get*():string = stdin.readLine() #.strip()
template `max=`*(x,y:typed):void = x = max(x,y)
template optPow{`^`(2,n)}(n:int) : int = 1 shl n
template If*(ex:untyped):untyped = (if not(ex) : continue)
proc enumerate[T](arr:seq[T]): seq[tuple[i:int,val:T]] =
  result = @[]; for i,a in arr: result &= (i,a)

let
  N = get().parseInt()
  A = get().split().map(parseInt).sorted(cmp,Descending)
  M = get().parseInt()
  B = get().split().map(parseInt).sorted(cmp,Descending)

var state = newSeqWith(2^N,0)
for n in 0 ..< 2^N:
  for ia in 0 ..< N:
    If: (n and 2^ia) == 2^ia
    state[n] += A[ia] # 各状態の体積の和

proc getOKState(b:int): IntSet =
  result = initIntSet()
  for i in state.enumerate().filterIt(b-it.val >= 0).mapIt(it.i):
    result.incl(i)

var ans = B[0].getOKState()
if 2^N-1 in ans:
  echo 1
  quit()
for i,b in B[1..^1]:
  var n_ans : IntSet
  n_ans.assign(ans)
  for x in b.getOKState().items:
    for y in ans.items:
      If: (x and y) == 0
      n_ans.incl(x xor y)
  ans = n_ans
  if 2^N-1 in ans:
    echo i + 2
    quit()
echo -1