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: Runtime Error)

import java.util.Arrays;
import java.util.Scanner;

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

        int n = sc.nextInt();
        int[] as = new int[n];
        for (int i = 0; i < n; i++) {
            as[i] = sc.nextInt();
        }
        System.out.println(Arrays.toString(as));

        int count = 1;
        int previnc = as[0] - as[1];
        for (int i = 2; i < n; i++) {
            int inc = as[i - 1] - as[i];
            if (previnc == 0) {
                previnc = inc;
                continue;
            }
            if (inc == 0) {
                continue;
            }
            // 符号が変わったら増やす
            if (0 < previnc && inc < 0 || previnc < 0 && 0 < inc) {
                previnc = 0;
                count++;
            }
        }

        System.out.println(count);
    }
}