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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

int main () {
  int N;
  cin >> N;
  vector<int> a(N);
  for(int i = 0; i < N; i++) {
    cin >> a.at(i);
  }
  bool u = false, d = false;
  int count = 1;
  for(int i = 0; i < N-1; i++) {
    if (u == false && d == false && a.at(i) < a.at(i+1)) u = true;
    else if (u == false && d == false && a.at(i) > a.at(i+1)) d = true;
    else if (u == true && a.at(i) > a.at(i+1)) {
      count++;
      u = false;
    }
    else if (d == true && a.at(i) < a.at(i+1)) {
      count++;
      d = false;
    }
  }
  cout << count << endl;
}