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 Java (OpenJDK 1.8.0) (judge verdict: Accepted)


import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);

		int n = sc.nextInt();

		int a[] = new int[n];

		for(int i = 0; i < n; i++){
			a[i] = sc.nextInt();
		}

		int mode = 0;
		int count = 1;

		for(int i = 1; i < n; i++){
			if(mode == 0){
				if(a[i] > a[i - 1]){
					mode = 1;
				}
				else if(a[i] < a[i - 1]){
					mode = 2;
				}
			}
			else if(mode == 1 && a[i] < a[i - 1]){
				mode = 0;
				count++;
			}
			else if(mode == 2 && a[i] > a[i - 1]){
				mode = 0;
				count++;
			}
		}

		System.out.println(count);
	}
}