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def calculate_changes(a):
    errors = 0
    is_positive_number = a[0] >= 0

    for i in range(0, len(a)-1, 2):
        if is_positive_number and a[i] - a[i+1] <= 0:
            errors += 1
            is_positive_number = False
            continue
        if not is_positive_number and a[i] - a[i + 1] >= 0:
            errors += 1
            is_positive_number = True

    return errors


n = int(input())
__a = input().split()
a = [int(number) for number in __a]

print(calculate_changes(a))