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 JavaScript (Node.js 12.16.1) (judge verdict: Accepted)

function Main(input) {
  const arr = input.trim().split('\n')[1].split(' ');
  let count = 1;
  let flg = true;
  let trend;

  for (let i = 0; i < arr.length - 1; i++) {
    const diff = arr[i] - arr[i + 1];
    let curr;

    if (diff === 0) continue;
    if (diff > 0) curr = 0;
    if (diff < 0) curr = 1;
    if (flg) {
      trend = curr;
      flg = false;
      continue;
    }

    if (curr === trend) {
      continue;
    } else {
      flg = true;
      trend = curr;
      count += 1;
    }
  }

  console.log(count);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));