N=int(raw_input())
A=map(int,raw_input().split())
M=int(raw_input())
B=map(int,raw_input().split())
B.sort()
B.reverse()
dp=[(-1,-1) for i in range(1<<N)]
dp[0]=(0,0)

def rec(mask):
    global dp,N,A,M,B
    if dp[mask][0]!=-1:
        return dp[mask]
    a,b=100,100
    for i in range(N):
        if (mask&(1<<i)) != 0:
            nmask = mask-(1<<i)
            n_box,rest=rec(nmask)
            na,nb=100,100
            if rest >= A[i]:
                na,nb=n_box,rest-A[i]
            elif n_box<M and B[n_box] >=A[i]:
                na,nb=n_box+1,B[n_box]-A[i]
            else:
                na,nb=100,100
            if a > na or( a==na and  b < nb ):
                a,b=na,nb
    dp[mask]=(a,b)
    #print format(mask,'b'), a,b
    return a,b


a,b=rec( (1<<N)-1 )
if a >N:
    print -1
else:
    print a