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 <bits/stdc++.h>

using namespace std;

#define foru(i, l, r) for(register int i = l; i <= r; i++)
#define ford(i, r, l) for(register int i = r; i >= l; i--)

int N, A[100005];

int main() {
  //  freopen("a.in", "r", stdin);
  //  freopen("a.out", "w", stdout);
  scanf("%d", &N);
  foru(i, 1, N) scanf("%d", &A[i]);
  int now_len = 0, Ans = 0, type = -1;
  now_len++;
  foru(i, 2, N) {
    if(now_len == 1) {
      now_len++;
      if (A[i] == A[i - 1])
        type = -1;
      else
        type = A[i] > A[i - 1];
      continue;
    }
    if(A[i] == A[i - 1]) {
      now_len++;
      continue;
    }
    if(type < 0) {
      now_len++;
      type = A[i] > A[i - 1];
      continue;
    }
    if(A[i] > A[i - 1] && type) {
      now_len++;
      continue;
    }
    if (A[i] < A[i - 1] && !type) {
      now_len++;
      continue;
    }
    Ans++, now_len = 1;
  }
  printf("%d\n", Ans + 1);
  return 0;
}