Seats

There are N seats in a row, numbered 1, 2, …, N.

The state of the seats is given by a string S of length N consisting of # and .. If the i^th character of S is #, it means seat i is occupied; if it is ., seat i is unoccupied.

Find the number of integers i between 1 and N-2, inclusive, that satisfy the condition that seats i and i+2 are occupied, and seat i+1 is unoccupied.

Constraints

1 ≤ N ≤ 2 × 10⁵

S is a string of length N consisting solely of # and ..

Input

The input consists of two lines.

On the first line, there will be a single integer N

On the second line, there will be the string S

Output

Output a single integer, representing the number of integers i between 1 and N-2, inclusive, that satisfy the condition that seats i and i+2 are occupied, and seat i+1 is unoccupied.

Subtasks

Subtask 1 (100%): No further constraints.

Subtask 2 (0%): Sample Testcases

Sample Input 1

6
#.##.#

Sample Output 1

2

Explanation

i = 1 and 4 both satisfy the condition.

Sample Input 2

1
#

Sample Output 2

0

Sample Input 3

9
##.#.#.##

Sample Output 3

3