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++14 (GCC 5.4.1) (judge verdict: Accepted)

// バケット法による解
#include <iostream>
using namespace std;

int main() {
    int N;
    int d[110];
    cin >> N;
    for (int i = 0; i < N; ++i) cin >> d[i];

    int num[110] = {0};  // バケット
    for (int i = 0; i < N; ++i) {
        num[d[i]]++;  // d[i] が 1 個増える
    }

    int res = 0;  // 答えを格納
    for (int i = 1; i <= 100; ++i) {  // 1 <= d[i] <= 100 なので 1 から 100 まで探索
        if (num[i]) {  // 0 より大きかったら
            ++res;
        }
    }
    cout << res << endl;
}