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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

int main()
{
  int64_t N, prev_a, a, da = 0, cnt = 1;
  cin >> N;
  cin >> prev_a;
  for (int i = 1; i < N; i++)
  {
    cin >> a;
    if ((a > prev_a && da < 0) || ((a < prev_a && da > 0)))
    {
      cnt++;
      da = 0;
    }
    else if (da == 0)
    {
      da = a - prev_a;
    }
    prev_a = a;
  }
  cout << cnt << endl;
}