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: Wrong Answer)

#include<stdio.h>

int main()
{
  int n;
  long long a[100001];
  int i;
  int ans=1;
  scanf("%d",&n);
  for(i=0;i<n;i++){
    scanf("%lld",&a[i]);
  }
  if(n<=2){
    printf("%d",1);
    return 0;
  }
  for(i=0;i<n-2;i++){
    if(a[i]<=a[i+1] && a[i+1]<=a[i+2]){
    }
    if(a[i]>=a[i+1] && a[i+1]>=a[i+2]){
    }
    else{
      i++;
      ans++;
    }
  }
  printf("%d",ans);
  return 0;
}