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 (GCC 9.2.1) (judge verdict: Accepted)

#include<stdio.h>

int main()
{
  int n;
  int a[100001];
  int i;
  int ans=0;
  scanf("%d",&n);
  for(i=0;i<n;i++){
    scanf("%d",&a[i]);
  }
  for(i=0;i<n;i++){
    while(i+1<n && a[i]==a[i+1]) i++;
    if(i+1<n && a[i]<a[i+1]){
      while(i+1<n && a[i]<=a[i+1]) i++;
    }
    else if(i+1<n && a[i]>a[i+1]){
      while(i+1<n && a[i]>=a[i+1]) i++;
    }
    ans++;
  }
  printf("%d",ans);
  return 0;
}