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

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