import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

n = ni()
a, b = na()
p = na()
for i in range(n):
    if p[i] == 1:
        c = 1
        d = 0
    elif p[i] == 2:
        c = 0
        d = 1
    else:
        c = 1
        d = 1
    # print(a, b)
    if a < c or b < d:
        print(i + 1)
        exit()
    a -= c
    b -= d
print(-1)