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: Accepted)

(let* ((n (make-hash-table :test #'equal)))
  (loop :for k :from 1 :upto (read)
        :for j := (read-line)
        :if (not (gethash j n)) :do(setf (gethash j n) 1))
  (princ (hash-table-count n)))