Problems > Count Local Maxima

Count Local Maxima

Difficulty: 900 2000 ms 128 MB

implementation

A position i (1 < i < N) is a local maximum if ai is strictly greater than both neighbours. Count the local maxima.

Input: the first line has an integer N; the second line has N integers separated by spaces.

Output: one integer — the number of local maxima.

Constraints:

  • 1 ≤ N ≤ 2000
  • −109 ≤ ai ≤ 109

Sample Tests

Input 1
6
1 3 2 5 4 1
Output 1
2
Input 2
3
1 2 3
Output 2
0

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