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)

// スタックサイズ: 100MB

#include <iostream>
#include <fstream>
#include <vector>
#include <map>
#include <unordered_map>
#include <string>
#include <cmath>
#include <cstdio>
#include <algorithm>
#include <functional>
#include <numeric>
#include <iomanip>
#include <queue>
#include <list>
#include <set>
using namespace std;

typedef int64_t ll;
typedef vector<ll> vll;
typedef pair<ll, ll> pll;
const ll INF = 1000000000000000000;
#define fori(i, a, b) for (ll i = (a); i < (b); ++i)
#define ford(i, a, b) for (ll i = (b - 1); (a) <= i; --i)
#define rep(i, n) fori(i, 0, n)
#define all(v) (v).begin(), (v).end()
#define fst first
#define snd second
ll pw(ll x, ll y) { ll r = 1;  rep(i, y) { r *= x; }; return r; }




int main() {
	ll N;
	cin >> N;

	vll d(N);
	rep(i, N) cin >> d[i];
	sort(all(d));
	d.erase(unique(all(d)), d.end());
	cout << d.size() << endl;
}