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 (Clang 10.0.0) (judge verdict: Wrong Answer)

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

int main() {
    int n;
    scanf("%d", &n);


    int** p = (int**)malloc(sizeof(int*) * n);
    for (int i = 0; i < n; ++i)
    {
        p[i] = (int*)malloc(sizeof(int) * 10);
        scanf("%s", p[i]);
    }

    char tmp[10] = { 0 };
    int count = 0;
    for (int k = 0; k < n; k++) {
        if (p[k] == "empty") {
            continue;
        }
        strcpy(tmp, p[k]);
        for (int j = k; j < n; j++) {
            if (p[j] == tmp) {
                p[j] = "empty";
            }
        }
        count++;
    }
    printf("%d", count);
    return 0;
}