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: Accepted)

import numpy as np

N = int(input())
A = list(map(int, input().split()))

count = 1
direction = 0
temp = A[0]
for i in range(1, N):
    diff = A[i] - temp
    if diff != 0:
        if direction == 0:
            direction = np.sign(A[i] - temp)
        else:
            if np.sign(A[i] - temp) != direction:
                count += 1
                direction = 0
    temp = A[i]

print(count)