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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)


import java.util.Scanner;

public class Main{

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		int input_count = sc.nextInt();

		int[] array = new int[input_count];

		int array_count = 0;
		int pre_num = 0;

		for(int i = 0;i < array.length;i++){
			int num = sc.nextInt();

			if(pre_num == num){
				continue;
			}

			pre_num = num;
			array[array_count] = num;
			array_count++;
		}


		int i_is_up = 0;

		int line_count = 1;

		for(int i = 0;i < array.length - 1;i++){
			int sign = Integer.signum(array[i + 1] - array[i]);

			if(i_is_up == 0){
				i_is_up = sign;
				continue;
			}

			if(i_is_up != sign){
				line_count++;
				i_is_up = 0;
			}
		}

		System.out.println(line_count);

		sc.close();
	}

}