def solve():
	n = int(input())
	a, b = [int(x) for x in input().split()]
	p = [int(x) for x in input().split()]
	for i in range(n):
		a -= p[i] in [1, 3]
		b -= p[i] in [2, 3]
		if a < 0 or b < 0:
			return i + 1
	return -1

print(solve())