import itertools as it N = int(raw_input()) A = map(int,raw_input().split()) M = int(raw_input()) _B = sorted(map(int,raw_input().split()),reverse = True) ans = M+1 for order in it.permutations(A,N): B = _B[:] i = j = 0 while i < N and j < M: if B[j] >= order[i]: B[j] -= order[i] i += 1 else: j += 1 ans = min(ans, j+1) print ans if ans < M+1 else -1