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 <bits/stdc++.h>

using namespace std;

int n, ans;

int main()
{
	int a, i, p1, p2;
	
	scanf("%d", &n);
	
	p1 = p2 = -1;
	
	for(i=0; i<n; i++){
		scanf("%d", &a);
		if(p2 == -1) ans ++;
		else if(p1 != -1){
			if((p1 < p2 && p2 > a) || (p1 > p2 && p2 < a)){
				ans ++;
				p1 = -1, p2 = a;
			}
		}
		
		if(p2 != a) p1 = p2; p2 = a;
	}
	
	printf("%d\n",ans);
	
	return 0;
}