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 Ruby (2.3.3) (judge verdict: Accepted)

=begin
  －－－－－－－－－－－－－－
  n = ループ回数
  A = 数列
  ans = 分割回数(答)
  pre = 前回の数値(A[i-1])
  vec = 前回の不等号 (< == 1 , > == -1)
  －－－－－－－－－－－－－－
  1: 一つ前の数値と比べる
  2: A[i-1] 小なり A[i] の場合 
    2.1: vec が 1 ならそのまま
    2.2: vec が -1 なら ans += 1 vec = 0
  3: A[i-1] 大なり A[i] の場合
    3.1: vec が -1 ならそのまま
    3.2: vec が 1　なら ans += 1 vec = 0
  4: A[i] イコール A[i+1]　なら nil
  5: pre = A[i]
=end

n = gets.to_i
A = gets.split.map(&:to_i)

pre = A.first
vec = 0
ans = 0

A[1..-1].each{|v|
  if pre < v
    if vec == -1
      ans += 1
      vec = 0
    else
      vec = 1
    end
  elsif pre > v
    if vec == 1
      ans += 1
      vec = 0
    else
      vec = -1
    end
  else
    nil
  end
  pre = v
}

puts ans + 1