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: Wrong Answer)

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
const int N=100010;
int n,ans=1;
int a[N];
int main()
{
	scanf("%d",&n);
	for(int k=1;k<=n;k++)
		scanf("%d",&a[k]);
	bool bo;
	if(a[1]<=a[2]) bo=1;
	else bo=0;
	for(int k=3;k<=n;k++)
	{
		if(bo==1)
		{
			if(a[k]<a[k-1])
			{	
				ans++;
				k++;
				if(a[k]<=a[k+1]) bo=1;
				else bo=0;
			}
		}
		else
		{
			if(a[k]>a[k-1])
			{
				ans++;
				k++;
				if(a[k]<=a[k+1]) bo=1;
				else bo=0;
			}
		}
	}
	printf("%d",ans);
	return 0;
}