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(void){
    // Your code here!
    int n;
    scanf("%d",&n);
    
    int s1=0;
    int s2=0;
    int now=0;
    int nut=1;
    int count=0;
    
    for(int i=0;i<n;i++){
        scanf("%d",&s1);
        
        if(i==0){
            
        }else if(nut==1){
            if(s1==s2){
                
            }else if(s1>s2){
                nut=0;
                now=1;
            }else if(s1<s2){
                nut=0;
                now=-1;
            }
        }else{
            if((s1-s2)*now>=0){
                
            }else if((s1-s2)*now<0){
                count++;
                nut=1;
            }
        }
        s2=s1;
    }
    printf("%d\n",count+1);
}