Problem:
Score : 300 points

Problem Statement

There are N slimes lining up from left to right. The colors of these slimes will be given as a string S of length N consisting of lowercase English letters. The i-th slime from the left has the color that corresponds to the i-th character of S.

Adjacent slimes with the same color will fuse into one larger slime without changing the color. If there were a slime adjacent to this group of slimes before fusion, that slime is now adjacent to the new larger slime.

Ultimately, how many slimes will be there?

Constraints

1 \leq N \leq 10^5

|S| = N

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

N
S

Output

Print the final number of slimes.

Sample Input 1

10
aabbbbaaca

Sample Output 1

5

Ultimately, these slimes will fuse into abaca.

Sample Input 2

5
aaaaa

Sample Output 2

1

All the slimes will fuse into one.

Sample Input 3

20
xxzaffeeeeddfkkkkllq

Sample Output 3

10

Solution in Common Lisp (SBCL 2.0.3) (judge verdict: Accepted)

(defmacro read-to-list ()
  `(read-from-string
    (concatenate 'string "(" (read-line) ")")))

(defun solve (s &optional (res 0) (prev #\0))
  (if (null s)
      res
      (if (char-equal (first s)
                      prev)
          (solve (rest s) res (first s))
          (solve (rest s) (1+ res) (first s)))))


(defun main ()
  (let ((n (read))
        (s (concatenate 'list (read-line))))
    (format t "~a~%" (solve s))))


(main)