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 Rust (1.42.0) (judge verdict: Accepted)

use proconio::{input, fastout};

#[fastout]
fn main() {
    input! {
        n: usize,
        a: [i64; n]
    }
    let mut prev: i64 = a[0];
    let mut ans: i32 = 1;
    let mut deg: i8 = 0;
    for x in a {
        if deg==1 {
            if prev>x {
                ans += 1;
                deg = 0;
            }
        } else if deg==-1 {
            if prev<x {
                ans += 1;
                deg = 0;
            }
        } else {
            if prev<x {
                deg = 1;
            } else if prev>x {
                deg = -1;
            }
        }
        prev = x;
    }
    println!("{}", ans);
}