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: Wrong Answer)

#include <iostream>
#include <vector>

using namespace std;

int main()
{
  int n;
  vector<int> a;

  cin >> n;

  for ( int i = 0; i < n; i++ ) {
    int t; cin >> t;
    a.push_back( t );
  }

  int x = 1, flag;

  if ( n == 1 ) {
    cout << 1 << endl;
    return 0;
  }

  if ( a[0] < a[1] )
    flag = 1;
  else
    flag = 0;

  for ( int i = 1; i < n; i++ ) {
    if ( ( flag == 1 && a[i-1] > a[i] ) || ( flag == 0 && a[i-1] < a[i] ) ) {
      x++;
      if ( i == n-1 ) break;
      if ( a[i] < a[i+1] )
        flag = 1;
      else
        flag = 0;
    }
  }

  cout << x << endl;

  return 0;
}