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 (Clang 3.8.0) (judge verdict: Wrong Answer)

#include<stdio.h>

int main(){
	
	int N,A[100010],i,ans=1,B[100010],k=1;
	
	scanf("%d",&N);
	
	for(i=1;i<=N;i++){
		scanf("%d",&A[i]);
	}
	
	for(i=1;i<=N-1;i++){
		if(A[i]<A[i+1]){
			B[i]=1;
		}else if(A[i]>A[i+1]){
			B[i]=-1;
		}else {
			B[i]=0;
		}
	}
	
	while(k<=N-1){
		if(B[k]!=0&&B[k+1]!=0&&B[k]!=B[k+1]){
			ans++;
			k+=2;
		}else {
		k++;
	}
	}
	
	printf("\n%d\n\n",ans);
	
	
	
	
	return 0;
}