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 Pascal (FPC 3.0.4) (judge verdict: Time Limit Exceeded)

program train;
var 
    a : array[1..200000] of string;
    i, j, count, n : integer;
    b : array[1..200000] of integer;
begin
    readln(n);
    count := 0;
    for i := 1 to n do begin
        readln(a[i]);  
        b[i] := 1;
        end;
    for i := 1 to n do 
        for j := i+1 to n do
            if b[i] <> 0
                then if a[i] = a[j]
                    then b[j] := 0;
    for i := 1 to n do 
        count := count + b[i];
    write(count);
end.