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 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(void){
    int n;
    scanf("%d", &n);

    if(n==1){
        printf("1\n");
        return 0;
        }

    int a[n];
    for(int i=0; i<n; i++){
        scanf("%d", &a[i]);
    }
    //FtR

    int d, ans=1;
    //d==1 => incr., d==-1 => decr., d==0 => default.

    if(a[0]<a[1]){ d=1; }
    else if(a[0]>a[1]){ d=-1; }
    else{
        d==0;
        }

    for(int i=1; i<n-1; i++){
        if(d>=0&&a[i]<=a[i+1]){
            d=1;
        }
        else if(d<=0&&a[i]>=a[i+1]){
            d=-1;
        }
        else{
            ans++;
            d=0;
        }
    }

    printf("%d\n", ans);
    return 0;
}