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)

#include <bits/stdc++.h>
#define double long double
#define int long long
#define mi map<int,int>
#define pii pair<int,int>
#define low lower_bound
#define upp upper_bound
#define mod (int)1e9+7
#define inf (int)1e16
#define rep(i,n) for(int i=0;i<n;i++)
#define all(vec) vec.begin(),vec.end()
#define vsort(vec) sort(all(vec))
#define vrever(vec) reverse(all(vec));
#define vunsort(vec) sort(all(vec),greater<>());
#define bisea binary_search
#define cend cout<<endl;
#define F first
#define S second
#define P pair<int,int>
#define prique priority_queue<P,vector<P>,greater<P>>
using namespace std;
int n,d;
set<int>st;
signed main() {
  cin>>n;
  rep(i,n) {
    cin>>d;
    st.insert(d);
  }
  cout<<st.size()<<endl;
}