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 <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <algorithm>
#include <stdint.h>
#include <queue>
#include <bitset>
#include <iomanip>

#include <queue>
#include <cstdio>

#include <list>
#include <set>


#define PI (3.14159265358979323846)
#define INF (1e+9)
#define DIV_NUM (1000000007)

using namespace std;


bool seen[501][501];

int N,K;
int X, Y, Z;
int con;
//    string S;


char field[501][501];
int  dist[501][501];

typedef pair<int, int> P;
queue<P> que;


//typedef vector<vector<int>> v;
vector<double> v1;
vector<double> v2;


set<int> s1;


int main(){
  
  
    // input data
    int d = 0;


    cin >> N;

    for (int i = 0; i < N; i++) {
        cin >> d;
        s1.insert(d);
    }

    set<int>::iterator ite;;

    ite = s1.end();
 
    
    std::cout << *ite << "\n";

        return 0;

}