N,M = map(int,input().split())
S = []
for _ in range(M):
  S.append(int(input()))
S.append(-1)
S.append(N+1)
S.sort()  
P = 1

def Fib(n):    
    if n == 1:
        return 0
    elif n == 2:
        return 1
    else:
        return Fib(n-1)+Fib(n-2)
      
for i in range(M+1):
  P *= Fib(S[i+1]-S[i]) 

print(P%1000000007)