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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
class c
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        var a = Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
        int ans = 1;
        if (n > 2)
        {
            int x = 0, y = 0, z = 0;
            for (int i = 0; i < n; i++)
            {
                if (z != a[i])
                {
                    x = y;
                    y = z;
                    z = a[i];
                    if (x > 0 && (x < y && y > z || x > y && y < z))
                    {
                        ans++;
                        x = y = 0;
                    }
                }
            }
        }
        Console.WriteLine(ans);
    }
}