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: Accepted)

#include <stdio.h>

enum State { FIRST, INCREASE, DECREASE };

int main(void) {
	int N, i, A[2], count = 1, state = FIRST;

	scanf("%d", &N);
	scanf("%d", &A[0]);
	for (i = 0; i < N - 1; i++) {
		scanf("%d", &A[1]);
		switch (state) {
		case FIRST:
			if (A[0] < A[1])
				state = INCREASE;
			else if (A[0] > A[1])
				state = DECREASE;
			break;

		case INCREASE:
			if (A[0] > A[1]) {
				state = FIRST;
				count++;
			}
			break;

		case DECREASE:
			if (A[0] < A[1]) {
				state = FIRST;
				count++;
			}
			break;
		}
		A[0] = A[1];
	}

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