Problem:
Score : 300 points

Problem Statement

You are given an array A of length N.
Your task is to divide it into several contiguous subarrays.
Here, all subarrays obtained must be sorted in either non-decreasing or non-increasing order.
At least how many subarrays do you need to divide A into?

Constraints

1 \leq N \leq 10^5

1 \leq A_i \leq 10^9

Each A_i is an integer.

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N

Output

Print the minimum possible number of subarrays after division of A.

Sample Input 1

6
1 2 3 2 2 1

Sample Output 1

2

One optimal solution is to divide the array into [1,2,3] and [2,2,1].

Sample Input 2

9
1 2 1 2 1 2 1 2 1

Sample Output 2

5

Sample Input 3

7
1 2 3 2 1 999999999 1000000000

Sample Output 3

3

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

from math import ceil


def main():
    length = int(input())
    sequence = list(map(int, input().split()))
    count = 1
    before_val = sequence[0]
    if length > 2:
        delta = 1  # increase: 1, decrease: 0
        if sequence[1] < before_val:
            delta = 0
        before_val = sequence[1]
        for i in range(2, length):
            if before_val < sequence[i] and delta == 0:
                delta = 1
                count += 1
            elif sequence[i] < before_val and delta == 1:
                delta = 0
                count += 1
            before_val = sequence[i]
    print(ceil(count / 2) + 1)


if __name__ == '__main__':
    main()