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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        List<Integer> dList = new ArrayList<>();
        int answer = 0;
        while (true) {
            try {
                final String line = bufferedReader.readLine();
                if (line == null || line.length() == 0) {
                    break;
                }
                dList.add(Integer.parseInt(line));
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        int n = dList.get(0);
        dList.remove(0);
        dList.sort(Collections.reverseOrder());

        int old = 101;// di <= 100
        for (Integer d : dList) {
            if (d < old) {
                old = d;
                answer++;
            }
        }
        System.out.println(answer);
    }
}