Buggy python submission (verdict: Time Limit Exceeded):
def my_sign(n):
    return (n > 0) - (n < 0)
def kugiri(cnt, lst):
    if len(lst) <= 1:
        return cnt
    else:
        pm = lst[0]
        i = 1
        fl = 0
        while i < len(lst):
            if pm == lst[i]:
                i += 1
                continue
            else:
                fl = 1
                break
        if fl == 1:
            new_lst = []
            for j in range(i + 1, len(lst)):
                new_lst.append(lst[j])
            return kugiri(cnt + 1, new_lst)
        else:
            return cnt

N = int(input())
A_lst = [int(x) for x in input().split()]
cnt = 1
if N == 1:
    pass
else:
    S_lst = []
    for i in range(1, N):
        S_lst.append(my_sign(A_lst[i] - A_lst[i - 1]))
    for i in range(len(S_lst)):
        if i == 0 and S_lst[i] == 0:
            for j in range(len(S_lst)):
                if not S_lst[j] == 0:
                    S_lst[i] = S_lst[j]
        elif S_lst[i] == 0:
            S_lst[i] = S_lst[i - 1]
    cnt = kugiri(cnt, S_lst)
print(cnt)


Fixed submission:
def main():
    N = int(input())
    lst = [int(_) for _ in input().split()]
    last = lst[0]
    A = [last]
    for i in range(1, N):
        if lst[i] == last: continue
        last = lst[i]
        A.append(lst[i])
    left = right = output = 0
    while left < len(A):
        if left == len(A)-1:
            output += 1
            break
        if A[left+1] - A[left] > 0:
            while right < len(A)-1 and A[right] < A[right+1]:
                right += 1
        elif A[left+1] - A[left] < 0:
            while right < len(A)-1 and A[right] > A[right+1]:
                right += 1
        output += 1
        left = right + 1
        right = left
    print(output)
    return

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
N = int(input())
A_lst = [int(x) for x in input().split()]
B_lst =[]
for i in range(N - 1):
    B_lst.append(A_lst[i + 1] - A_lst[i])

def my_sign(n):
    return (n > 0) - (n < 0)

cnt = 1
i = 0
pm = my_sign(B_lst[0])
while True:
    if i >= len(B_lst) - 2:
        break
    else:
        if my_sign(B_lst[i + 1]) == 0:
            i += 1
            continue
        elif pm == my_sign(B_lst[i + 1]) or pm == 0:
            pm = my_sign(B_lst[i + 1])
            i += 1
            continue
        else:
            cnt += 1
            pm = my_sign(B_lst[i + 1])
            i +=2
print(cnt)


Fixed submission:
def main():
    N = int(input())
    lst = [int(_) for _ in input().split()]
    last = lst[0]
    A = [last]
    for i in range(1, N):
        if lst[i] == last: continue
        last = lst[i]
        A.append(lst[i])
    left = right = output = 0
    while left < len(A):
        if left == len(A)-1:
            output += 1
            break
        if A[left+1] - A[left] > 0:
            while right < len(A)-1 and A[right] < A[right+1]:
                right += 1
        elif A[left+1] - A[left] < 0:
            while right < len(A)-1 and A[right] > A[right+1]:
                right += 1
        output += 1
        left = right + 1
        right = left
    print(output)
    return

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
N = int(input())
A_lst = [int(x) for x in input().split()]
B_lst =[]
for i in range(N - 1):
    B_lst.append(A_lst[i + 1] - A_lst[i])

def my_sign(n):
    return (n > 0) - (n < 0)

cnt = 1
i = 0
pm = my_sign(B_lst[0])
while True:
    if i >= len(B_lst) - 1:
        break
    else:
        if my_sign(B_lst[i + 1]) == 0:
            i += 1
            continue
        elif pm == my_sign(B_lst[i + 1]) or pm == 0:
            pm = my_sign(B_lst[i + 1])
            i += 1
            continue
        else:
            cnt += 1
            pm = my_sign(B_lst[i + 1])
            i +=2
print(cnt)


Fixed submission:
def main():
    N = int(input())
    lst = [int(_) for _ in input().split()]
    last = lst[0]
    A = [last]
    for i in range(1, N):
        if lst[i] == last: continue
        last = lst[i]
        A.append(lst[i])
    left = right = output = 0
    while left < len(A):
        if left == len(A)-1:
            output += 1
            break
        if A[left+1] - A[left] > 0:
            while right < len(A)-1 and A[right] < A[right+1]:
                right += 1
        elif A[left+1] - A[left] < 0:
            while right < len(A)-1 and A[right] > A[right+1]:
                right += 1
        output += 1
        left = right + 1
        right = left
    print(output)
    return

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
N = int(input())
A_lst = [int(x) for x in input().split()]
B_lst =[]
for i in range(N - 1):
    B_lst.append(A_lst[i + 1] - A_lst[i])

def my_sign(n):
    return (n > 0) - (n < 0)

cnt = 1
i = 0
pm = my_sign(B_lst[0])
while True:
    if i >= len(B_lst) - 1:
        break
    else:
        if my_sign(B_lst[i + 1]) == 0:
            i += 1
            continue
        elif pm == my_sign(B_lst[i + 1]) or pm == 0:
            pm = my_sign(B_lst[i + 1])
            i += 1
            continue
        else:
            cnt += 1
            i +=2
print(cnt)


Fixed submission:
def main():
    N = int(input())
    lst = [int(_) for _ in input().split()]
    last = lst[0]
    A = [last]
    for i in range(1, N):
        if lst[i] == last: continue
        last = lst[i]
        A.append(lst[i])
    left = right = output = 0
    while left < len(A):
        if left == len(A)-1:
            output += 1
            break
        if A[left+1] - A[left] > 0:
            while right < len(A)-1 and A[right] < A[right+1]:
                right += 1
        elif A[left+1] - A[left] < 0:
            while right < len(A)-1 and A[right] > A[right+1]:
                right += 1
        output += 1
        left = right + 1
        right = left
    print(output)
    return

if __name__ == '__main__':
    main()