Problem:
Score : 300 points

Problem Statement

You drew lottery N times. In the i-th draw, you got an item of the kind represented by a string S_i.

How many kinds of items did you get?

Constraints

1 \leq N \leq 2\times 10^5

S_i consists of lowercase English letters and has a length between 1 and 10 (inclusive).

Input

Input is given from Standard Input in the following format:

N
S_1
:
S_N

Output

Print the number of kinds of items you got.

Sample Input 1

3
apple
orange
apple

Sample Output 1

2

You got two kinds of items: apple and orange.

Sample Input 2

5
grape
grape
grape
grape
grape

Sample Output 2

1

Sample Input 3

4
aaaa
a
aaa
aa

Sample Output 3

4

Solution in Common Lisp (SBCL 2.0.3) (judge verdict: Time Limit Exceeded)

(let ((n (read)))
     (declare (type fixnum n))
     (loop with arr = (make-array 10
                                  :initial-contents
                                  (loop repeat 10
                                        collect '()))
           repeat n
           do (let ((word (read-line)))
                   (if (not (find word (aref arr (1- (length word))) 
                                  :test #'string=))
                       (push word (aref arr (1- (length word))))))
           finally (format t "~A" (apply #'+
                                         (mapcar #'length
                                                 (coerce arr 'list))))))