import sequtils,strutils,strscans,algorithm,math,future,macros
template get*():string = stdin.readLine() #.strip()
import times

let
  N = get().parseInt()
  A = get().split().map(parseInt).sorted(cmp,Descending) # toy <20
  M = get().parseInt()
  B = get().split().map(parseInt).sorted(cmp,Descending) # box <20
var ans = newSeq[int]()
let start = cpuTime()
proc check(i:int,bs:seq[tuple[vol:int,use:bool]]):void =
  if i == A.len():
    ans &= bs.mapIt(it.use.int).sum()
    if cpuTime() - start > 0.003:
      echo ans.min()
      quit()
    return
  for j,b in bs:
    if b.vol < A[i] :
      if not b.use : break
      else: continue #!
    var nbs = bs
    nbs[j].vol -= A[i]
    nbs[j].use = true
    check(i+1,nbs)
  return
check(0,B.mapIt((it,false)))
if ans.len() > 0: echo ans.min()
else: echo -1