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: Accepted)

#include <math.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef unsigned long long int ull;
typedef long long int ll;
typedef long double ld;

// qsort に関数ポインタとして渡す関数
int compare_base(const void *b, const void *f) {
  return (strncmp(*(char **)b, *(char **)f, 10));
}

int main(void) {
  int scan; // scanf result
  int answer; // to output 
  int n; // to input 
  char **s;
  
  answer = 0;
  scan = scanf("%d", &n);
  s = (char **)malloc(sizeof(char *) * (n + 1));
  for (int i = 0; i < n; i++) {
    s[i] = (char *)malloc(sizeof(char) * 11);
    scan = scanf("%s", s[i]);
  }

  qsort((void *)s, n, sizeof(char *), compare_base);
  for (int i = 0; i < n; i++) {
    if (i == 0 || (i >= 1 && strncmp(s[i - 1], s[i], 10) != 0)) {
      answer++;
    }
  }

  printf("%d", answer);
  return (0);
}