import sys, math sys.setrecursionlimit(10**8) sys.set_int_max_str_digits(0) INF = 1e18 MOD = 998244353 from bisect import bisect_left, bisect_right from collections import deque, defaultdict, Counter from itertools import product, combinations, permutations, groupby, accumulate from heapq import heapify, heappop, heappush input = sys.stdin.readline def I(): return input().rstrip() def II(): return int(input().rstrip()) def IS(): return input().rstrip().split() def MII(): return map(int, input().rstrip().split()) def LI(): return list(input().rstrip()) def TII(): return tuple(map(int, input().rstrip().split())) def LII(): return list(map(int, input().rstrip().split())) def LSI(): return list(map(str, input().rstrip().split())) def GMI(): return list(map(lambda x: int(x) - 1, input().rstrip().split())) def kiriage(a, b): return (a+b-1)//b N = II() A, B = MII() P = LII() for i in range(N): p = P[i] if p == 1: A -= 1 elif p == 2: B -= 1 else: A -= 1 B -= 1 if A < 0 or B < 0: exit(print(i + 1)) print(-1)