N = int(input())
apple, banana = map(int, input().split())
orders = list(map(int, input().split))

for i in range(len(orders)):
	if orders[i] == 1:
		if apple == 0:
			print(i+1)
			exit()
		apple -= 1
	elif orders[i] == 2:
		if banana == 0:
			print(i+1)
			exit()
		banana -= 1
	else:
		if apple == 0 or banana == 0:
			print(i+1)
			exit()
		apple -= 1
		banana -= 1
print(-1)