Buggy python submission (verdict: Runtime Error):
# -*- coding: utf-8 -*-
MOD = 1000000007
N, M = map(int, input().split())
a = []
for _ in range(M):
    a.append(int(input()))


def getPatternNum(num):
    pattern = [0] * (num + 2)
    pattern[0] = 0
    for i in range(1, num + 2):
        if i == 0 or i == 1:
            pattern[i] = 1
            continue
        pattern[i] = (pattern[i - 2] + pattern[i - 1]) % MOD
    return pattern

def solve():
    # 階段の連続してる数のリスト
    stepsList = [0] * (M + 1)
    maxSteps = 0
    stepsList[0] = a[0]
    for j in range(1, M):
        stepsList[j] = a[j] - a[j - 1] - 1
        if stepsList[j] == 0:
            return 0
    stepsList[M] = N - a[M - 1]
    pattern = getPatternNum(max(stepsList) + 1)
    # こわれてるところ以外のパターンを掛ける
    # print("#", pattern)
    for k in range(len(stepsList)):
        if k == 0:
            total = pattern[stepsList[k]]
        else:
            total = (total * pattern[stepsList[k]]) % MOD
        # print("##", k, stepsList[k], pattern[stepsList[k]], total)

    return total


ans = solve()
print(ans)

Fixed submission:
N, M = map(int, input().split())
a = [int(input()) for _ in range(M)]
a.sort()
a.append(10 ** 9 + 7)

memo = [None] * (N + 1)
memo[0] = 1

idx = 0
for pos in range(1, N + 1):
    if a[idx] == pos:
        memo[pos] = 0
        idx += 1
        continue
    else:
        if pos > a[idx]:
            idx += 1
        #
        if pos == 1:
            memo[1] = (memo[0]) % (10 ** 9 + 7)
        else:
            memo[pos] = (memo[pos - 2] + memo[pos - 1]) % (10 ** 9 + 7)

# print("#", memo)
print(memo[-1])

Buggy python submission (verdict: Runtime Error):
# -*- coding: utf-8 -*-
MOD = 1000000007
N, M = map(int, input().split())
a = []
for _ in range(M):
    a.append(int(input()))


def getPatternNum(num):
    pattern = [0] * (num + 1)
    for i in range(num + 1):
        if i == 0 or i == 1:
            pattern[i] = 1
            continue
        pattern[i] = (pattern[i - 2] + pattern[i - 1]) % MOD
    return pattern


def solve():
    # 階段の連続してる数のリスト
    stepsList = [0] * (M + 1)
    maxSteps = 0
    stepsList[0] = a[0]
    for j in range(1, M):
        stepsList[j] = a[j] - a[j - 1] - 1
        if stepsList[j] == 0:
            return 0
    stepsList[M] = N - a[M - 1]
    pattern = getPatternNum(max(stepsList) + 1)
    # こわれてるところ以外のパターンを掛ける
    for k in range(len(stepsList)):
        if k == 0:
            total = pattern[stepsList[k] - 1]
        else:
            total = (total * pattern[stepsList[k] - 1]) % MOD
        # print("#", k, stepsList[k], pattern[stepsList[k] - 1], total)

    return total


ans = solve()
print(ans)

Fixed submission:
N, M = map(int, input().split())
a = [int(input()) for _ in range(M)]
a.sort()
a.append(10 ** 9 + 7)

memo = [None] * (N + 1)
memo[0] = 1

idx = 0
for pos in range(1, N + 1):
    if a[idx] == pos:
        memo[pos] = 0
        idx += 1
        continue
    else:
        if pos > a[idx]:
            idx += 1
        #
        if pos == 1:
            memo[1] = (memo[0]) % (10 ** 9 + 7)
        else:
            memo[pos] = (memo[pos - 2] + memo[pos - 1]) % (10 ** 9 + 7)

# print("#", memo)
print(memo[-1])

Buggy python submission (verdict: Runtime Error):
# -*- coding: utf-8 -*-
MOD = 1000000007
N, M = map(int, input().split())
a = []
for _ in range(M):
    a.append(int(input()))


def getPatternNum(num):
    pattern = [0] * num
    for i in range(num):
        if i == 0 or i == 1:
            pattern[i] = 1
            continue
        pattern[i] = (pattern[i - 2] + pattern[i - 1]) % MOD
    return pattern


def solve():
    # 階段の連続してる数のリスト
    stepsList = [0] * (M + 1)
    maxSteps = 0
    stepsList[0] = a[0]
    for j in range(1, M):
        stepsList[j] = a[j] - a[j - 1] - 1
        if stepsList[j] == 0:
            return 0
    stepsList[M] = N - a[M - 1]
    pattern = getPatternNum(max(stepsList) + 1)
    # こわれてるところ以外のパターンを掛ける
    for k in range(len(stepsList)):
        if k == 0:
            total = pattern[stepsList[k] - 1]
        else:
            total = (total * pattern[stepsList[k] - 1]) % MOD
        # print("#", k, stepsList[k], pattern[stepsList[k] - 1], total)

    return total


ans = solve()
print(ans)

Fixed submission:
N, M = map(int, input().split())
a = [int(input()) for _ in range(M)]
a.sort()
a.append(10 ** 9 + 7)

memo = [None] * (N + 1)
memo[0] = 1

idx = 0
for pos in range(1, N + 1):
    if a[idx] == pos:
        memo[pos] = 0
        idx += 1
        continue
    else:
        if pos > a[idx]:
            idx += 1
        #
        if pos == 1:
            memo[1] = (memo[0]) % (10 ** 9 + 7)
        else:
            memo[pos] = (memo[pos - 2] + memo[pos - 1]) % (10 ** 9 + 7)

# print("#", memo)
print(memo[-1])