import sys
import re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from copy import copy
import numpy as np
from numpy.fft import fft, ifft
from fractions import gcd
import math


def input(): return sys.stdin.readline().strip()


def INT(): return int(input())


def MAP(): return map(int, input().split())


def LIST(): return list(map(int, input().split()))


sys.setrecursionlimit(10 ** 9)
INF = float('inf')
MOD = 10 ** 9 + 7


def Fib(n):
    a, b = 0, 1
    if n == 1:
        return a
    elif n == 2:
        return b
    else:
        for i in range(n-2):
            a, b = b, a + b
        return b


n, m = MAP()

a = [INT() for _ in range(m)]

a.insert(0,0)
a.append(n)

ans=1
for i in range(len(a) - 1):
    p = a[i + 1] - a[i]+2
    ans *= Fib(p)
    #print(ans)

print(ans%MOD)
            
    




