import sys
sys.setrecursionlimit(100000)

def intinput(): return map(int,sys.stdin.readline().split())

fib={0:0,1:1,2:1}
for i in range(3,100003):
    fib[i]=fib[i-1]+fib[i-2]
  #  fib.append(fib[i-1]+fib[i-2])

n,m=intinput()
mod=10**9+7
a=[int(sys.stdin.readline()) for _ in range(m)]
if m!=0:
    l=[a[0]]
    for i in range(len(a)-1):
        l.append(a[i+1]-a[i]-1)
    l.append(n-a[-1])
    k=1
    for i in l:
        k=fib[i]*k%mod
    print(k%mod)
else:
    print(fib[n+1])