Problem:
Score : 200 points

Problem Statement

An X-layered kagami mochi (X ≥ 1) is a pile of X round mochi (rice cake) stacked vertically where each mochi (except the bottom one) has a smaller diameter than that of the mochi directly below it. For example, if you stack three mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, you have a 3-layered kagami mochi; if you put just one mochi, you have a 1-layered kagami mochi.

Lunlun the dachshund has N round mochi, and the diameter of the i-th mochi is d_i centimeters. When we make a kagami mochi using some or all of them, at most how many layers can our kagami mochi have?

Constraints

1 ≤ N ≤ 100

1 ≤ d_i ≤ 100

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
d_1
:
d_N

Output

Print the maximum number of layers in a kagami mochi that can be made.

Sample Input 1

4
10
8
8
6

Sample Output 1

3

If we stack the mochi with diameters of 10, 8 and 6 centimeters from bottom to top in this order, we have a 3-layered kagami mochi, which is the maximum number of layers.

Sample Input 2

3
15
15
15

Sample Output 2

1

When all the mochi have the same diameter, we can only have a 1-layered kagami mochi.

Sample Input 3

7
50
30
50
100
50
80
30

Sample Output 3

4

Solution in C (Clang 3.8.0) (judge verdict: Accepted)

// https://atcoder.jp/contests/abc085/tasks/abc085_b
// B - Kagami Mochi
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// 標準入力から改行かスペースまで読み取り、数字として返す
int get_num() {
    // 10文字+区切り文字までしか受け付けられない
    char s[11];
    int i, n;
    // scanf()の直後は改行が入力に残っているので、
    // 最初の改行は読み飛ばす
    do {
        s[0] = getchar();
    } while (s[0] == '\0' || s[0] == '\n');
    for (i = 1; i < sizeof(s); i++) {
        s[i] = getchar();
        if (s[i] == ' ' || s[i] == '\n') {
            s[i] = '\0';
            break;
        }
    }
    sscanf(s, "%d", &n);
    return n;
}

int main(void) {
    int d[100] = {0};
    int input;
    int n;
    int count = 0;
    n = get_num();

    for (int i = 0; i < n; i++) {
        input = get_num();
        if (d[input-1]==0){
            d[input-1] = 1;
            count++;
        }
    }
    
    printf("%d\n", count);
    
    return 0;
}