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 C (GCC 9.2.1) (judge verdict: Time Limit Exceeded)

#include<stdio.h>
#include<string.h>

int main(void) {
    int N, count = 0;
    scanf("%d", &N);
    char s[200000][10];
    for (int i = 0; i < N; i++) {
        scanf("%s", s[i]);
    }

    for (int i = 0; i < N; i++) {
        for (int j = i + 1; j < N; j++) {
            if (strcmp(s[i], s[j]) == 0) {
                if (s[j][0] != '\0'){
                    count++;
                    s[j][0] = '\0';
                }
            }
        }
    }
    printf("%d\n", N - count);
    return 0;
}