N = int(input())
A, B = list(map(int,input().split()))
p = list(map(int,input().split()))

ans = -1

for i in range(N):
	if p[i] & 1:
		A -= 1
	if p[i] & 2:
		B -= 1
	
	if A < 0 or B < 0:
		ans = i+1
		break

print(ans)