Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)

n, m, *a = map(int, open(0).read().split())
dp = [0] * (n + 1)
ok = [True] * (n + 1)

for i in a:
    ok[i] = False


def count(n):
    if ok[n]:
        if n < 2:
            return 1
        if dp[n] != 0:
            return dp[n]
        dp[n] = (count(n - 1) + count(n - 2)) % (10**9 + 7)
        return dp[n]
    else:
        return 0


print(count(n))


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)

n, m, *a = map(int, open(0).read().split())
dp = [0] * (n + 1)
ok = [True] * (n + 1)

for i in a:
    ok[i] = False


def count(n):
    if ok[n]:
        if n < 2:
            return 1
        if dp[n] != 0:
            return dp[n]
        dp[n] = (count(n - 1) + count(n - 2)) % (10**9 + 7)
        return dp[n]
    else:
        return 0


print(count(n))


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)

n, m, *a = map(int, open(0).read().split())
dp = [0] * (n + 1)
ok = [True] * (n + 1)

for i in a:
    ok[i] = False


def count(n):
    if n < 2:
        return 1
    if dp[n] != 0:
        return dp[n]
    dp[n] = (count(n - 1) * ok[n - 1] + count(n - 2) * ok[n - 2]) % (10**9 + 7)
    return dp[n]


print(count(n))


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)

n, m, *a = map(int, open(0).read().split())
memo = [0] * (n+ 1)


def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = (count(n - 1)*(n-1 not in a) + count(n - 2)*(n-2 not in a) )%(10**9+7)
    return memo[n]

print(count(n))


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


def count(n):
    if n < 2:
        return 1
    return count(n - 1) + count(n - 2)


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from functools import reduce
from operator import mul


def cmb(n, r):
    r = min(n - r, r)
    if r == 0:
        return 1
    over = reduce(mul, range(n, n - r, -1))
    under = reduce(mul, range(1, r + 1))
    return over // under


def stair(r):
    con = 0
    for i in range(r // 2 + 1):
        con += cmb(r - i, i)
    return con


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * stair(i - c - 2) % (10**9 + 7)
    c = i
print(ans)


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from scipy.special import comb


def stair(r):
    con = 0
    for i in range(r // 2 + 1):
        con += comb(r - i, i, exact=True)
    return con


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n+1)
c = -1
ans = 1
for i in a:
    ans = ans * stair(i - c - 2) % (10**9 + 7)
    c = i
print(ans)


Fixed submission:
#!/usr/bin/env python3
import sys

sys.setrecursionlimit(1000000)


memo = [0]*(10**5+1)
def count(n):
    if n < 2:
        return 1
    if memo[n] != 0:
        return memo[n]
    memo[n] = count(n-1) + count(n-2)
    return memo[n]


n, m, *a = map(int, open(0).read().split())
if sum(a[i + 1] == a[i] + 1 for i in range(m - 1)) > 0:
    print(0)
    exit()

a.append(n + 1)
c = -1
ans = 1
for i in a:
    ans = ans * count(i - c - 2) % (10**9 + 7)
    c = i
print(ans)