// yukicoder: 50 おもちゃ箱
// 2019.6.2 bal4u

#include <stdio.h>
#include <stdlib.h>

#if 1
#define gc() getchar_unlocked()
#else
#define gc() getchar()
#endif
int in()    // 非負整数の入力
{
	int n = 0, c = gc();
	do n = 10 * n + (c & 0xf); while ((c = gc()) >= '0');
	return n;
}

int a[15], N;
int b[15], M;
int ans;

void showperm(char *p)
{
	int i, j, s;

	j = 0; for (i = 1; i < ans && i <= M; i++) {
		if (a[p[j]] > b[i]) return;
		s = 0;
		while (j < N && a[p[j]] + s <= b[i]) s += a[p[j++]];
		if (j >= N) {
			if (i < ans) ans = i;
			return;
		}
	}
}

// Kの数{ 1,2,3,4,5,6,7,8,9 } の順列を生成する K!個
void genperm(int K)
{
	int k, t;
	char c[12], *pc, *q;
	static char p[12] = { 1,1,1,1 };

	q = p, pc = c;
	for (k = 1; k <= K; ) *q++ = *pc++ = k++;  // 1 2 3 のように１から
	k = 1, pc = c;
	do {
		t = *(p + k);
		*(p + k) = *(q = p + ((k & 1) ? *pc : 0));
		*q = t;
		showperm(p);
		k = 1, pc = c;
		while (*pc == 0) *pc++ = k++;
		(*pc)--;
	} while (k < K);
}

int cmp(const void *a, const void *b) { return *(int *)b - *(int *)a; }

int main()
{
	int i;
	
	N = in(); for (i = 1; i <= N; i++) a[i] = in();
	qsort(a+1, N, sizeof(int), cmp); a[N+1] = 100;
	M = in(); for (i = 1; i <= M; i++) b[i] = in();
	qsort(b+1, M, sizeof(int), cmp);

	ans = 100;
	if (a[1] <= b[1]) genperm(N);
	if (ans > M) ans = -1;
	printf("%d\n", ans);
	return 0;
}