#pragma comment(linker, "/STACK:102400000,102400000")
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <cmath>
#include <string>
#include <vector>
#include <cstdio>
#include <cctype>
#include <cstring>
#include <sstream>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#define lson root<<1,l,mid
#define rson root<<1|1,mid+1,r
#define Key_Value ch[ch[root][1]][0]
#define DBN1(a)           cerr<<#a<<"="<<(a)<<"\n"
#define DBN2(a,b)         cerr<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<"\n"
#define DBN3(a,b,c)       cerr<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<"\n"
#define DBN4(a,b,c,d)     cerr<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<"\n"
#define DBN5(a,b,c,d,e)   cerr<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<", "<<#e<<"="<<(e)<<"\n"
#define DBN6(a,b,c,d,e,f) cerr<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<", "<<#e<<"="<<(e)<<", "<<#f<<"="<<(f)<<"\n"
#define clr(a,x) memset(a,x,sizeof(a))
#define pb push_back
#define ALL(x) x.begin(),x.end()
using namespace std;
typedef long long ll;
const int maxn=100000+5;
const int INF=0x3f3f3f3f;
const int P=1000000007;
const double PI=acos(-1.0);
template<typename T>
inline T read(T&x){
    x=0;int _f=0;char ch=getchar();
    while(ch<'0'||ch>'9')_f|=(ch=='-'),ch=getchar();
    while(ch>='0'&&ch<='9')x=x*10+ch-'0',ch=getchar();
    return x=_f?-x:x;
}
template <class T1, class T2>inline void gmax(T1 &a,T2 b){if (b>a) a=b;}
template <class T1, class T2>inline void gmin(T1 &a,T2 b){if (b<a) a=b;}
/*int n,u,v,root,in[maxn],fa[maxn];
bool vis[maxn];
vector<int>G[maxn];
queue<int>S;
void dfs(int u){
    if (G[u].size()==0){
        S.push(u);
        return;
    }
    sort(ALL(G[u]));
    for (int i=0;i<(int)G[u].size();i++){
        dfs(G[u][i]);
    }
}
void print(int u){
    if (!vis[u]) printf("%d\n",u),vis[u]=true;
    else return;
    if (fa[u]!=0) print(fa[u]);
    else return;
}
int main(){
    read(n);
    for (int i=1;i<n;i++){
        read(u),read(v);
        in[v]++;
        G[u].pb(v);
        fa[v]=u;
    }
    for (int i=1;i<=n;i++){
        if (in[i]==0){
            root=i;
            break;
        }
    }
    dfs(root);
    while (!S.empty()){
        print(S.front());
        S.pop();
    }
    return 0;
}*/
/*const int N=1e5+10;
struct _{
    int a,b;
    bool operator<(const _&rhs)const{
        if (a==rhs.a) return b>rhs.b;
        return a>rhs.a;
    }
}k[N];
int n,H;
bool cmp(const _&a,const _&b){
    return a.b>b.b;
}
int main(){
    read(n),read(H);
    int mxa=0,mxb=0;
    for (int i=1;i<=n;i++) mxa=max(mxa,read(k[i].a)),mxb=max(mxb,read(k[i].b));
    if (mxa>=H || mxb>=H) return puts("1"),0;
    sort(k+1,k+1+n);
    sort(k+2,k+1+n,cmp);
    int cnt=0;
    if (k[1].a<k[1].b) H-=k[1].b,cnt++;
    if (H<=0) printf("%d\n",cnt);
    else{
        for (int i=2;i<=n;i++){
            if (k[i].b<k[1].a){
                break;
            }
            else{
                H-=k[i].b;
                cnt++;
                if (H<=0) break;
            }
        }
        if (H<=0) printf("%d\n",cnt);
        else printf("%d\n",cnt+(H/k[1].a+(H%k[1].a==0?0:1)));
    }
    return 0;
}*/
/*int n,y;
int main(){
    read(n),read(y);
    for (int i=0;i<=n;i++){
        for (int j=0;j+i<=n;j++){
            int k=n-j-i;
            if (10000*i+5000*j+1000*k==y){
                return printf("%d %d %d\n",i,j,k),0;
            }
        }
    }
    puts("-1 -1 -1");
    return 0;
}*/
int main(){
    int n;
    set<int>SS;
    read(n);
    for (int d;n--;){
        read(d);
        SS.insert(d);
    }
    cout<<SS.size()<<endl;
    return 0;
}


Measured memory_bytes: 256