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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <vector>

using namespace std;

int main() {
	int n;
	cin >> n;
	vector<long long int> a(n);
	int ans = 1;
	for (int i = 0; i < n; i++) {
		cin >> a[i];
	}
	if (n > 1) {
		int k = 0;
		if (a[0] < a[1]) {
			k = 1;
		}
		else if (a[0] > a[1]){
			k = 2;
		}
		for (int i = 2; i < n; i++) {
			if (a[i - 1] < a[i]) {
				if (k == 2) {
					ans++;
					k = 0;
				}
				else {
					k = 1;
				}
			}
			else if (a[i - 1] > a[i]) {
				if (k == 1) {
					ans++;
					k = 0;
				}
				else {
					k = 2;
				}
			}
		}
	}
	cout << ans << endl;
	return 0;
}