n = int(input())
a, b = list(map(int, input().split()))
for i, p in enumerate(list(map(int, input().split()))):
    if p != 2:
        a -= 1
    if p != 1:
        b -= 1
    if a < 0 or b < 0:
        print(i+1)
        break
else:
    print(-1)