n,m = map(int,input().split())
brokensteps = set([int(input()) for x in range(m)])
dp = [0] * (n+1)
for i in range(n+1):
    if i in brokensteps:
        dp[i] = 0
        continue
    
    elif i <= 1:
        dp[i] = 1

    else:
        dp[i] = (dp[i-1] + dp[i-2])%(10**9+7)

print(dp)