T = 10 ** 9 + 7

def f(patterns, s1, s2):
    import math
    count = 0
    for s11, s22 in zip(s1, s2):
        if s11 == "0" and s22 == "1":
            count += 1
        elif s11 == "1" and s22 == "0":
            patterns = 0
            break

    return patterns * math.factorial(count) % T


def main():
    import sys
    n, k = input().split()
    n = int(n)
    k = int(k)
    patterns = 1
    if k != 0:
        checkpoint = [format(0, "b").zfill(n)] + \
                    list(map(lambda x: format(x, "b").zfill(n), sorted(list(map(int,input().split()))))) + \
                         [format(2**n-1,"b").zfill(n)]
    else:
        checkpoint = [format(0, "b").zfill(n), format(2**n-1, "b").zfill(n)]
    for i in range(1, k + 2):
        patterns = f(patterns, checkpoint[i-1], checkpoint[i])
    print(patterns)







if __name__ == "__main__":
    import sys
    import os
    if len(sys.argv) > 1:
        if sys.argv[1] == "-d":
            filename = "input1.txt"
            fd = os.open(filename, os.O_RDONLY)
            os.dup2(fd, sys.stdin.fileno())
            main()
    else:
        main()