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 Python (3.4.3) (judge verdict: Wrong Answer)

# 整数の入力
n=int(input())
a=list(map(int, input().split()))

p=1
flag=0 #増加中なら1,減少中なら0

for i in range(1,n):
  if a[i-1]<a[i]:
    if flag>=0:
      flag=1
    if flag==-1:
      flag=1
      p+=1
  if a[i-1]>a[i]:
    if flag<=0:
      flag=-1
    if flag==1:
      flag=-1
      p+=1
print(p)