Buggy python submission (verdict: Runtime Error):
import numpy as np

N, M = map(int, input().split())
stairs_exist = np.ones(N+1)

for c in range(M):
    stairs_exist[int(input())] = 0
    
steps = np.zeros(N+1)
steps[0] = 1
for i in range(N):
    for j in range(i+1, min(N+1, i+3)):
        if stairs_exist[j]:
            steps[j] += steps[i]
            
print(int(steps[-1] % (10 ** 9 + 7)))

Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])

Buggy python submission (verdict: Runtime Error):
import numpy as np

N, M = map(int, input().split())
stairs_exist = np.ones(N+1)

for c in range(M):
    stairs_exist[int(input())] = 0
    
steps = np.zeros(N+1)
steps[0] = 1
for i in range(N):
    for j in range(i+1, min(N+1, i+3)):
        if stairs_exist[j]:
            steps[j] += steps[i]
            
print(int(steps[-1]))

Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])

Buggy python submission (verdict: Runtime Error):
N, M = map(int, input().split())

stairs = []

for i in range(M):
    stairs.append(int(input()))
path = []
index = 1
if stairs[-1] == N-1:
    path.extend([1, 0])
    index += 1
else:
    path.extend([1, 1])
# caluclate from N-2 step (second last)

if N >= 2:
    for n in range(2, N):
        if N - n != stairs[-index]:
#             print(n, N - n, index, stairs[-index])
            path.append(path[n-2] + path[n-1])
        else:
            path.append(0)
            index += 1
    print((path[-1] + path[-2]) % (10**9+7)) 
#     print(path)
elif N < 2:
    print(1)
        

Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])

Buggy python submission (verdict: Runtime Error):
import numpy as np

N, M = map(int, input().split())
a = [int(input()) for i in range(M)]

ans = np.zeros(N + 1)
ans[N] = 1
broken_a = np.zeros(N)
for a_ in a:
    broken_a[a_] = 1
if broken_a[N-1] != 1:
    ans[N - 1] = 1


for i in range(2, N + 1):
    if broken_a[N - i] != 1:
        ans[N - i] = (ans[N - i + 1] + ans[N - i + 2])
    else:
        ans[N - i] = 0
print(int(ans[0] % (10 ** 9 + 7)))



Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])

Buggy python submission (verdict: Runtime Error):
import numpy as np

N, M = map(int, input().split())
a = [int(input()) for i in range(M)]

ans = np.zeros(N + 1)
ans[N] = 1

if N - 1 not in a:
    ans[N - 1] = 1

for i in range(2, N + 1):
    if N - i not in a:
        ans[N - i] = (ans[N - i + 1] + ans[N - i + 2])
    else:
        ans[N - i] = 0
        
print(int(ans[0] % (10 ** 9 + 7)))

Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])

Buggy python submission (verdict: Runtime Error):
import numpy as np

N, M = map(int, input().split())
a = [int(input()) for i in range(M)]

ans = np.zeros(N + 1)
ans[N] = 1

if N - 1 not in a:
    ans[N - 1] = 1

print(ans[N])

for i in range(2, N + 1):
    if N - i not in a:
        ans[N - i] = (ans[N - i + 1] + ans[N - i + 2])
    else:
        ans[N - i] = 0
        
print(int(ans[0] % (10 ** 9 + 7)))

Fixed submission:
N, M=map(int, input().split())
A = [int(input()) for _ in range(M)]
mod = 10**9 + 7
step = [1]*(N+1)

for a in A:
    step[a]=0
for i in range(2, N+1):
    step[i]=(step[i-1]+step[i-2])%mod*step[i]
print(step[-1])