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)

def main(argv)
  n = gets.chomp.to_i
  a = gets.chomp.split(' ').map(&:to_i)
  
  b = [0] * (n - 1)
  (n - 1).times{ |i| b[i] = a[i + 1] <=> a[i] }
  b.delete(0)
  
  i = 0
  c = 1
  d = b[0]
  while i < b.size do
    if b[i] != d then
      c += 1
      i += 1
      d = b[i]
    end
    i += 1
  end

  puts c.to_s
end

if self.to_s == 'main' then
  main(ARGV)
end