https://www.acwing.com/problem/content/4320/

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
using namespace std;
const int N = 110;
int a[N];
int main(){
    int n;
    cin>>n;
    for(int i=1;i<=n;i++)
    cin>>a[i];
    sort(a+1,a+n+1);
    int cnt=0;
    for(int i=1;i<=n;i++)
    if(a[i]!=a[i-1]) cnt++;//如果是a[i]与a[i+1]作比较的话，到最后一位就会和0比较，答案多出一个
    cout<<cnt;
    return 0;
}