#### C
from functools import reduce
from operator import mul
n,m = map(int,input().split())
a = [int(input()) for _ in range(m)]
MOD = 10 ** 9 + 7
def fib(n):
    if n == 1:
        return 0
    elif n == 2:
        return 1
    else:
        return fib(n-1) + fib(n-2)
   
a.append(n+1)
cnt = []
prev = 0
for i in a:
    tmp = fib(i+1-prev)
    cnt.append(tmp)
    prev = i+1
    
print(reduce(mul,cnt)%MOD)