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

for i in range(N):
    if P[i] == 1:
        A -= 1
    if P[i] == 2:
        B -= 1
    if P[i] == 3:
        A -= 1
        B -= 1
    if A == -1 or B == -1:
        print(i+1)
        exit(0)
print(-1)