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 a;
  cin >> a;
  vector<int> vec(a);
  int ans = 0;
  for (int i = 0; i < a; i++) cin >> vec.at(i);
  if (a == 1) ans++;
  for (int i = 0; i < a - 1; i++) {
    if (vec[i] == vec[i + 1]) continue;
    else if (vec[i] < vec[i + 1]) {
      ans++;
      while (vec[i] <= vec[i + 1] && i < a) i++;
      if (i == a - 2 && vec[i] > vec[i + 1]) ans++;
    }
    else if (vec[i] > vec[i + 1]) {
      ans++;
      while (vec[i] >= vec[i + 1] && i < a) i++;
      if (i == a - 2 && vec[i] < vec[i + 1]) ans++;
    }
  }
  cout << ans << endl;
}